The Global Hypersonic Race
Avangard launch
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Ph.D. in Political Science, Research Fellow at the Diplomatic Academy of the Ministry of Foreign Affairs, Director of the Emerging Technologies and Global Security Project at PIR-Center
Prominent Western politicians have launched a global discussion about the risks associated with Russia developing hypersonic weapons. Arms control experts are attempting to estimate the potential of these new weapons, but attempts at this stage are hindered by the absence of important technical data and the lack of specialized terminology in this field.
Federal Minister for Foreign Affairs of Germany Heiko Maas attempted to take the lead in discussing the destabilizing new technology. In March 2019, he hastily organized the “2019. Capturing Technology. Rethinking Arms Control” international conference in Berlin. In his opening speech, Maas said: “Manoeuvrable missiles travelling at many times the speed of sound barely leave time for considered human responses. The fact that we are not just talking about science fiction here is demonstrated by Russia’s announcement that the first Avangard systems will be entering service this year. I would therefore also like to seize this conference as an opportunity to establish an international missiles dialogue that takes into account both the challenges posed by new technologies and the dangers of their proliferation. The experts gathered here today could form the backbone of this kind of global Missile Dialogue Initiative.”
In the United States, where hypersonic technology has already been developing at a rapid pace, including as part of the Prompt Global Strike programme, Putin’s announcement was used as a pretext for investing more in the Pentagon’s projects. “We have lost our technical advantage in hypersonics [but] we have not lost the hypersonics fight,” said Vice Chairman of the Joint Chiefs of Staff General Paul Selva. Meanwhile, Under Secretary of Defense for Research and Engineering Mike Griffin, for his part, has identified hypersonics as his top priority and called for an industrial base to be established that could support the development and production of thousands of deterrence hypersonic vehicles.
China has been no stranger to this “war of words,” with several fantastic reports emanating from the country about “successful tests of hypersonic flight vehicles,” the creation of a material capable of withstanding temperatures of up to 3000 degrees Celsius, and even the development of a universal engine that can accelerate a vehicle from zero to hypersonic flight. Japan has stated its intent to create a High-Speed Gliding Missile, an equivalent of Russia’s Avangard.
Minister of the Armed Forces of France Florence Parly has announced the country’s plans to use the ASN4G supersonic air-to-surface cruise missile as the baseline for the V-MaX supersonic glider that could travel at a speed of over 6000 km/h. The project is being led by ArianeGroup, a joint venture between Airbus and Safran, and the first test flight could take place in late 2021.
Hypersonic missiles have several obvious advantages over ballistic missiles. First, they follow significantly shallower trajectories, so ground-based radars detect them later into the flight. Second, thanks to their maneuvering, high speed and unpredictable trajectory, the enemy cannot be certain of the hypersonic vehicle’s target, whereas the trajectory of a ballistic missile is currently fairly easy to calculate. Third, ballistic missile interception experiments have been conducted since the 1960s, and there are plenty of reports on successful trial intercepts. However, intercepting a high-speed maneuvering atmospheric target is extremely difficult and is believed to be impossible at present. Also, the mass production of hypersonic vehicles is expected to be cheaper than that of ballistic missiles. Despite the challenges associated with developing scram engines, such jets have virtually no moving parts and their cross-sections represent special configuration tubing. According to analysts at the U.S. company Capital Alpha Partners, “If hypersonic weapons can be produced with unit costs of $2 million, or less, they will impact some of the outyear weapons plans. A weapon that travels at Mach 5, or faster, and that can maneuver will see strong U.S. demand in the later part of this decade.” Finally, the kinetic energy of a hypersonic missile is so high that its release will be enough to destroy certain types of targets even without using a charge. This gives experts reason to state that hypersonic missiles might become an alternative to nuclear weapons in certain situations.
As for the shortcomings of hypersonic missiles, experts point out that they cannot offer high target accuracy because it is almost impossible to fit such a missile with a homing head, and its high speed will result in an increase in targeting error. A hypersonic vehicle is believed to have a CER of between 30 and 50 meters. Furthermore, high-speed missiles will have a large infrared signature due to frictional skin heating, making them easily detectable by IR sensors. Designers will need to find a compromise between the high impact speed and the high probability of standoff detection. Also, a scramjet-powered missile must be initially accelerated to a speed of about Mach 3. This complicates the use of such weapons, which require a rocket booster or a high-speed air-launch platform. Experts believe that, due to a plethora of technological problems, hypersonic weapons currently have a relatively limited effective range (some 1000km for scramjet-powered missiles). However, the veil of secrecy surrounding this type of weaponry provokes rumors and excessive fears, and this destabilizing factor could prompt the enemy to resort to a pre-emptive strike.
Russia’s breakthrough in the hypersonic weapons race may have shaken the global balance of forces, but it has not reshaped it. The United States is not far behind Russia technologically, and may even be ahead in certain aspects of hypersonic weapons, including when it comes to making combined-cycle or hybrid propulsion systems for hypersonic vehicles that would allow a reusable reconnaissance/strike vehicle to be created. Nevertheless, the Russian achievements came as an unpleasant surprise for all the leading world powers.
The situation appears different for those nations that do not command massive nuclear arsenals. The Russian example opens a window of opportunities for them. Hypersonic weapons may appear to be an excellent solution for ensuring a decisive military advantage over a technically lacking adversary. Those countries lagging behind in the arms race may perceive hypersonic weapons as a critical and potentially disarming threat to an unfriendly neighbor.
Prominent Western politicians have launched a global discussion about the risks associated with Russia developing hypersonic weapons. Arms control experts are attempting to estimate the potential of these new weapons, but attempts at this stage are hindered by the absence of important technical data and the lack of specialized terminology in this field.
The discussion of the threats posed by hypersonic weapons was triggered by President of the Russian Federation Vladimir Putin, who in his address to the Federal Assembly on March 1, 2018, described the impressive capabilities of Russia’s new Avangard and Kinzhal strategic missile systems as follows: “The glide vehicle strikes its target like a meteorite, like a fireball, with its surface temperature reaching between 1600 and 2000 degrees Celsius, while remaining completely controllable at the same time.”
Brave New World Without INF Treaty
Federal Minister for Foreign Affairs of Germany Heiko Maas attempted to take the lead in discussing the destabilizing new technology. In March 2019, he hastily organized the “2019. Capturing Technology. Rethinking Arms Control” international conference in Berlin. In his opening speech, Maas said: “Manoeuvrable missiles travelling at many times the speed of sound barely leave time for considered human responses. The fact that we are not just talking about science fiction here is demonstrated by Russia’s announcement that the first Avangard systems will be entering service this year. I would therefore also like to seize this conference as an opportunity to establish an international missiles dialogue that takes into account both the challenges posed by new technologies and the dangers of their proliferation. The experts gathered here today could form the backbone of this kind of global Missile Dialogue Initiative.”
However, the subsequent discussion at the conference demonstrated that many of the participants were unfamiliar with the topic of hypersonic weapons. Recognized experts on missile control proved unprepared to hold a substantive conversation about hypersonic technology. As a result, the dialogue was reduced to discussing the INF Treaty.
At the end of the conference, the ministers of foreign affairs of Germany, the Netherlands and Sweden signed a political declaration stressing the “need to build a shared understanding of how technologically enhanced military capabilities may change the character of warfare and how this will influence global security.”
In the United States, where hypersonic technology has already been developing at a rapid pace, including as part of the Prompt Global Strike programme, Putin’s announcement was used as a pretext for investing more in the Pentagon’s projects. “We have lost our technical advantage in hypersonics [but] we have not lost the hypersonics fight,” said Vice Chairman of the Joint Chiefs of Staff General Paul Selva. Meanwhile, Under Secretary of Defense for Research and Engineering Mike Griffin, for his part, has identified hypersonics as his top priority and called for an industrial base to be established that could support the development and production of thousands of deterrence hypersonic vehicles.
Mike White, the Pentagon’s assistant director for hypersonics, announced that the department had a three-step plan for the development of hypersonic weapons that involves investing generously in offensive capabilities, then in defensive systems, and finally, at least ten years from now, in reusable airborne hypersonic vehicles. The Pentagon’s spending on hypersonic projects has increased from $201 million in 2018 to $278 million in 2019, and the overall cost of the program is estimated at $2 billion.
China has been no stranger to this “war of words,” with several fantastic reports emanating from the country about “successful tests of hypersonic flight vehicles,” the creation of a material capable of withstanding temperatures of up to 3000 degrees Celsius, and even the development of a universal engine that can accelerate a vehicle from zero to hypersonic flight. Japan has stated its intent to create a High-Speed Gliding Missile, an equivalent of Russia’s Avangard.
Minister of the Armed Forces of France Florence Parly has announced the country’s plans to use the ASN4G supersonic air-to-surface cruise missile as the baseline for the V-MaX supersonic glider that could travel at a speed of over 6000 km/h. The project is being led by ArianeGroup, a joint venture between Airbus and Safran, and the first test flight could take place in late 2021.
In the meantime, the global expert community has yet to come up with a clear scientific definition for the term “hypersonic vehicle.” Hypersonic flight is conventionally understood to mean atmospheric flight at speeds higher than Mach 5, that is, five times the speed of sound. The second important feature of a hypersonic aircraft is its ability to maneuver with the use of aerodynamic forces, rather than merely adjusting the target accuracy. This entails longer atmospheric flight times and greater susceptibility to the destructive factors associated with atmospheric flight.
At present, only a handful of countries are close to creating effective hypersonic weapons. Hypersonic weapons engineers are faced with some very unique technical challenges. To begin with, there is the problem of ensuring controlled and sustained flight in a rarefied atmosphere whose density varies with altitude. Among other things, this creates difficulties for propulsion systems that consume oxygen.
Also, the friction created by the hypersonic airflow around the vehicle’s surface generates a sheath of ionized plasma, with the nose fairing temperature reaching up to 3000 degrees Celsius. Even vehicles made of ultra-heat-resistant alloys or composites lose their shape and original aerodynamic characteristics due to the heating and ablation. For example, the U.S. Lockheed SR-71 Blackbird high-altitude supersonic reconnaissance aircraft would become 10cm longer in flight owing to thermal expansion, and fuel would seep from its seams on landing.
Controlling a hypersonic vehicle from launch to target impact is a separate problem, as the plasma sheath blocks radio signals. Solving this problem requires complex and expensive research. Even US engineers have not yet found a solution to this problem.
Should We Be Afraid of Prompt Global Strike?)
Another challenge is linked to the fact that the plasma sheath significantly complicates navigation, which for a strike vehicle must be autonomous, prompt and very accurate. Plasma makes electro-optical and radio-frequency homing impossible. Inertial navigation systems cannot provide the required accuracy at long distances. A solution to this problem has yet to be found.
The traditional types of aviation fuel (jet fuel and methane) are unsuitable at hypersonic speeds. A hypersonic vehicle needs a special kind of fuel. Also, a universal propulsion engine capable of accelerating a vehicle from zero to hypersonic speeds has not yet been created. At present, militaries have to make do with rocket boosters or supersonic aircraft to accelerate vehicles to speeds at which their supersonic combustion ramjet engines can be engaged.
When it comes to the flight mode, there are three different types of hypersonic vehicles. The first type is an unpowered glide vehicle, which rides a ballistic missile to an altitude of approximately 100km, separates, and performs a maneuverable flight in the upper atmospheric layer at speeds between Mach 8 and Mach 28. By skip-gliding along the atmosphere like a skipping stone along the water surface, such a vehicle can increase its flight range by several times. The second type is a scramjet-powered vehicle, which can only fly in the atmosphere because its engine needs oxygen. The third type is a quasi-ballistic or semi-ballistic missile that mainly follows a shallow ballistic trajectory but can also maneuver to evade enemy missile defenses. One example here is the Russian Iskander-M missile, which flies at hypersonic speeds of between 2100 and 2600 m/sec (Mach 6 to Mach 7) at an altitude of 50km.
Experts sometimes use the term “aeroballistic.” However, this definition is not applied to the speed of flight, but rather to the mode of travel: namely, it implies a combined mode of partially traveling along a ballistic trajectory and partially employing aerodynamic control surfaces and jet vanes for steering. An aeroballistic vehicle does not necessarily have to be hypersonic, as the term can also be applied to slower vehicles, although it is now widely used in the context of the hypersonic Kinzhal and Iskander-M missiles.
Recognized experts on missile control proved unprepared to hold a substantive conversation about hypersonic technology.
Hypersonic vehicles have one distinct feature which traditional exo-atmospheric ballistic missiles do not. While most ballistic missiles develop speeds of dozens of Machs (i.e., they also travel at hypersonic speeds), they are not described as hypersonic unless they or their warheads are capable of aerodynamic maneuvering in the atmosphere.
Some ballistic missile warheads are capable of terminal trajectory corrections. They are not classed as hypersonic vehicles, since the purpose of their maneuvering is not to increase the flight range or evade an anti-missile attack, but merely to reduce the circular error probable (CEP).
All hypersonic vehicles can be subdivided into five categories depending on their mission:
- Manned aircraft (the first and so far only example here is the U.S. North American X-15, which set the world airspeed record of Mach 6.72 in 1967)
- Unmanned vehicles (mainly experimental projects such as the Boeing X-43, which reached Mach 9.6 in 2004)
- Scramjet-powered hypersonic missiles (such as the Russian 3M22 Zircon)
- Hypersonic glide vehicles (the Russian Avangard or the U.S. Advanced Hypersonic Weapon)
- Air- or ground-launched spaceplanes (the Soviet Buran and U.S. Space Shuttle vehicles, which reach speeds of Mach 25 upon re-entry).
Military hypersonic vehicles fall into the following three categories:
1. Reconnaissance vehicles
At present, only one purely reconnaissance hypersonic vehicle is known to be under development: the Lockheed Martin SR-72, which can theoretically travel at speeds of up to 7400 km/h. This vehicle is expected to be better at monitoring mobile missile systems than reconnaissance satellites. It could also eventually be equipped to carry a charge for a pinpoint strike.
Another experimental orbital hypersonic vehicle is the Boeing X-37B. Although little is known about its intended mission, it could also serve as a reconnaissance platform.
2. Hypersonic kill vehicles
Scramjet-powered hypersonic cruise missiles that can be launched by an aircraft, a sea-surface ship or a submarine (the Russian 3M22 Zircon or the U.S. X-51A Waverider, which is currently under development) can be used to destroy enemy missile early warning systems, anti-aircraft and anti-missile defenses, airfields, hardened command posts and critical facilities.
Glide vehicles (the Russian Avangard; the U.S. Lockheed Martin Falcon, HIFiRE and HSSW/TBG [High-Speed Strike Weapon/Tactical Boost Glide]; and the Chinese WU-14/DF-ZF) are primarily intended as nuclear strike weapons.
Quasi-ballistic missiles (the Russian Kinzhal and Iskander-M; the Indian Shaurya tactical missile; and the Chinese DF-21D anti-ship ballistic missile) are relatively difficult to detect by radar thanks to their shallow trajectory. Their warheads can change trajectory, so enemy missile defenses cannot calculate the exact target, and the warhead’s maneuverability considerably complicates interception.
3. Hypersonic interceptors
These are surface-to-air missiles designed to intercept ballistic missile warheads, normally in their terminal, atmospheric phase of trajectory. The most advanced interceptors can engage ballistic missiles at exo-atmospheric altitudes and even shoot down low-orbit satellites.
To stand a chance of intercepting a ballistic target, an interceptor must not only develop a high speed, but also launch promptly and maneuver actively. U.S. RIM-161 SM-3 Block IIA missiles of the Aegis Ballistic Missile Defense System can travel at speeds of up to Mach 15.25; the Russian S-400 48N6DM missiles have a speed of Mach 7.5, and the future S500 77N6-N1 missiles will be able to reach speeds of up to Mach 21.
Advantages of Hypersonic Missiles
The Collapse of the INF Treaty as a Motivation?
Hypersonic missiles have several obvious advantages over ballistic missiles. First, they follow significantly shallower trajectories, so ground-based radars detect them later into the flight. Second, thanks to their maneuvering, high speed and unpredictable trajectory, the enemy cannot be certain of the hypersonic vehicle’s target, whereas the trajectory of a ballistic missile is currently fairly easy to calculate. Third, ballistic missile interception experiments have been conducted since the 1960s, and there are plenty of reports on successful trial intercepts. However, intercepting a high-speed maneuvering atmospheric target is extremely difficult and is believed to be impossible at present. Also, the mass production of hypersonic vehicles is expected to be cheaper than that of ballistic missiles. Despite the challenges associated with developing scram engines, such jets have virtually no moving parts and their cross-sections represent special configuration tubing. According to analysts at the U.S. company Capital Alpha Partners, “If hypersonic weapons can be produced with unit costs of $2 million, or less, they will impact some of the outyear weapons plans. A weapon that travels at Mach 5, or faster, and that can maneuver will see strong U.S. demand in the later part of this decade.” Finally, the kinetic energy of a hypersonic missile is so high that its release will be enough to destroy certain types of targets even without using a charge. This gives experts reason to state that hypersonic missiles might become an alternative to nuclear weapons in certain situations.
Shortcomings of Hypersonic Missiles
As for the shortcomings of hypersonic missiles, experts point out that they cannot offer high target accuracy because it is almost impossible to fit such a missile with a homing head, and its high speed will result in an increase in targeting error. A hypersonic vehicle is believed to have a CER of between 30 and 50 meters. Furthermore, high-speed missiles will have a large infrared signature due to frictional skin heating, making them easily detectable by IR sensors. Designers will need to find a compromise between the high impact speed and the high probability of standoff detection. Also, a scramjet-powered missile must be initially accelerated to a speed of about Mach 3. This complicates the use of such weapons, which require a rocket booster or a high-speed air-launch platform. Experts believe that, due to a plethora of technological problems, hypersonic weapons currently have a relatively limited effective range (some 1000km for scramjet-powered missiles). However, the veil of secrecy surrounding this type of weaponry provokes rumors and excessive fears, and this destabilizing factor could prompt the enemy to resort to a pre-emptive strike.
Challenges for International Security and Stability
The Pentagon’s spending on hypersonic projects has increased from $201 million in 2018 to $278 million in 2019, and the overall cost of the program is estimated at $2 billion.
The U.S. expert community has carefully studied the potential of Russian hypersonic weapons in terms of how they could affect the balance of forces and concluded that, in general, they do not pose an existential threat to major nuclear powers. Thus, fitting Avangard missiles with glide vehicles will not increase the size of the Russian nuclear arsenal, nor will it extend the effective range of the missiles, their range of action or their strike speed. The United States and other nuclear powers will still be able to respond to a Russian nuclear attack.
U.S. experts admit that maneuvering hypersonic vehicles are almost impossible to intercept. However, given that the U.S. missile defense system has very limited intercept capabilities when it comes even to Russian ballistic missiles, the introduction of Avangard hypersonic missiles changes little in the nuclear war scenario. For the United States, this is more of a technological challenge, with which both the Pentagon and the White House are fairly unhappy. Dominance in military technology has remained a priority for the United States for decades, ever since the launch of the first Soviet satellite. Therefore, the news of Russia’s hypersonic achievements does not sit well with Washington. At the same time, it has provided the United States with an opportunity to study the possibility of extending missile defense to near space. Megawatt laser weapons are believed to be capable of destroying both ballistic and hypersonic missiles. The current level of U.S. technology already allows for equipping different types of ground transport with lasers generating in excess of 50kW of power, while sea-based lasers can generate over 150kW. Under the current trend, laser power increases tenfold every three years. In this sense, within five years, we can expect U.S. laser technology to reach a level that where the Pentagon may be confident in the possibility of building lasers that are capable of shooting down hypersonic devices. The next step will then be to deploy laser weapons in the Earth’s orbit.
In light of the above, the emergence of hypersonic weapons will introduce a number of destabilizing factors for international security. First, countries possessing such weapons will have an asymmetric advantage over other developing countries. Second, it will trigger the deployment of the space-based laser component of the missile defense system. Third, it will provoke a new global arms race, including with regard to laser weapons, hypersonic anti-missile systems, cyber-weapons, railguns and unmanned delivery platforms for strike weapons. Moreover, for non-nuclear powers, hypersonic missiles may become a serious instrument of deterrence or power projection. It should also be noted that hypersonic missiles could be used in a pre-emptive strike against an enemy whose main weapons are situated within their effective reach (at present, within a radius of up to 1000km). That is, the deployment of hypersonic weapons can be considered as a critical threat to the country’s immediate neighbors. Finally, there are global risks to the Missile Technology Control Regime (MTCR). The secret hunt for missile components such as fuel, alloys, electronics and airframe blueprints has never stopped. In the new environment, even those countries that are signatories to the MTCR are interested in obtaining prompt global strike technologies.
The current leaders of hypersonic weapons research are, in addition to Russia, the United States and China.
China
Is There Life After Arms Control Death?
Despite its ambitious statements, China has not yet rolled out a reliable prototype of a hypersonic vehicle. Chinese engineers have developed the YJ-12 supersonic anti-ship cruise missile, but the country’s military currently only has subsonic ground-based cruise missiles in service. It may be the case that Beijing hopes to leap from subsonic straight to hypersonic, skipping supersonics altogether.
China is believed to be working on at least two hypersonic programs. Since 2014, it has been testing the DF-ZF (dubbed Wu-14 in the United States) hypersonic glide vehicle complete with the DF-17 medium-range ballistic missile for the launch vehicle (eventually to be replaced by the DF-31 missile). The second project, the air-launched CH-AS-X-13 missile, is primarily intended against aircraft carriers. According to a representative of the Chinese Academy of Engineering, the Institute of Mechanics has created a turbine-based combined-cycle engine capable of accelerating a vehicle to Mach 6.
United States
As part of the High Speed Strike Weapon (HSSW) program, the Defense Advanced Research Projects Agency (DARPA) and the United States Air Force are working on three hypersonic concepts. The Tactical Boost Glide (TBG) combat vehicle riding a solid-fuel rocket booster, under development by Lockheed Martin and Raytheon, is planned as an equivalent to Russia’s Avangard. The Boeing Hypersonic Air-Breathing Weapon Concept (HAWC) will have a combined-cycle engine (the turbine will accelerate the vehicle to Mach 2, after which the scramjet will further propel it to hypersonic speeds). According to some reports, the vehicle may be reusable. Northrop Grumman Corporation is working to design the combined-cycle Advanced Full Range Engine (AFRE) for HAWC under a contract with DARPA. Finally, the reusable unmanned craft under development as part of the HyRAX project and the XS-1 Experimental Spaceplane program will be used as an inexpensive launch vehicle to insert dual-use satellites into low-Earth orbits.
The HSSW program is aimed at designing and testing a hypersonic strike vehicle by 2020. The key specifications include speeds of Mach 6 to 10, an effective range of over 1000km, a CEP of under 5m and a variety of warhead types (penetrator, HE-fragmentation or cluster).
Hypersonic weapons may appear to be an excellent solution for ensuring a decisive military advantage over a technically lacking adversary.
The U.S. Air Force Research Laboratory is looking into the possibility of creating a combined-cycle propulsion system for reusable vehicles, including by way of integrating scramjets with reheated bypass turbojets.
In addition to DARPA, hypersonic weapons are being developed by the United States Army Space and Missile Defense Command in conjunction with the Sandia National Laboratory under the Advanced Hypersonic Weapon project, which calls for the creation of a hypersonic glide vehicle with a precision terminal guidance system.
Russia’s breakthrough in the hypersonic weapons race may have shaken the global balance of forces, but it has not reshaped it. The United States is not far behind Russia technologically, and may even be ahead in certain aspects of hypersonic weapons, including when it comes to making combined-cycle or hybrid propulsion systems for hypersonic vehicles that would allow a reusable reconnaissance/strike vehicle to be created. Nevertheless, the Russian achievements came as an unpleasant surprise for all the leading world powers.
The situation appears different for those nations that do not command massive nuclear arsenals. The Russian example opens a window of opportunities for them. Hypersonic weapons may appear to be an excellent solution for ensuring a decisive military advantage over a technically lacking adversary. Those countries lagging behind in the arms race may perceive hypersonic weapons as a critical and potentially disarming threat to an unfriendly neighbor.
In the art of war, uncertainty often drives progress. As the leading analytical centers are working to collect relevant information and understand the scale of possible threats, politicians and militaries are approving investment in new defense programs. A new item on defense budgets around the world has appeared.
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Don't put the mankind back to 1980's
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The Collapse of the INF Treaty as a Motivation?Despite the attempts of Russian and U.S. sides to find common ground on the Intermediate-Range Nuclear Forces (INF) Treaty, it appears that the agreement will cease to exist this year. So what next?
Is There Life After Arms Control Death?For all the importance of limiting and reducing nuclear arms, the priority task for all should be to prevent a nuclear war