On October 20, President Donald Trump announced that the United States will leave the Intermediate-range Nuclear Forces (INF) Treaty. The INF Treaty, signed in 1987, prohibits the United States and the Soviet Union from possessing, testing and deploying ground-launched cruise and ballistic missiles of ranges between 500 and 5,500 kilometers, missiles which were designed to fight a nuclear war in Europe. It was a milestone in international arms control as the Soviet Union and the United States got rid of a major source of crisis instability and insecurity for both states. The decision to leave this treaty is a major departure from previous American arms control policies. The president justified his decision to leave the treaty, citing the Russia’s history of violating the INF treaty since 2014 and stating that it undermines American interests in the Asia-Pacific region to counter China. Regardless of the merits of leaving the INF Treaty, the US decision to leave the treaty will most likely lead to a breakdown in US-Russian arms control cooperation, changes in US nuclear strategy in the Asia-Pacific region, and US deployment of weapons systems that were not permitted in the treaty.
With the collapse of the INF Treaty, the only remaining U.S.-Russian arms control agreement would be the New START agreement. While this agreement expires in 2021, there were proposals to renew the New START treaty for another five years prior to the announcement of the US leaving the INF Treaty. The breakdown in cooperation between these two nations concerning the INF Treaty can cause cooperation efforts over New START to cease. Such failure is likely as prominent arms-control skeptic John Bolton, who pushed for the US to leave the INF Treaty, is likely to oppose renewing New START. If both New START and INF treaties end, then both Russia and the United States will not have any restrictions on their nuclear arsenals anymore.
Another major change in US policy after leaving the INF Treaty will likely occur in reaction to China’s nuclear posture. China, since it was not a party to the INF Treaty, can deploy and utilize intermediate-range missiles and weapons systems. 95% of China’s missiles are estimated to be ballistic missiles in violation of INF Treaty restrictions, if China was a signatory to the INF Treaty. China has the world’s largest Ballistic Weapons program, which the United States can’t counter due to the limitations placed on the US by the INF. With the US no longer in the INF Treaty, the US has no treaty restriction on placing ground-based missile assets in the Asia-Pacific region and, thus, it can expand its nuclear umbrella to counter China’s nuclear posture in the region.
Furthermore, without the restrictions placed on the United States for developing and deploying certain weapons systems under the treaty, the United States is now able to pursue research of new technologies that would have gone against the letter of the treaty, and it could also lead to less exotic solutions that the INF Treaty would have banned outright. A major example is that the US Army’s Precision Strike Missile would be modified to hit targets within the missiles ranges that were banned by the treaty instead of being capped below the artificial limit. Another major change in missile deployments is expected to occur within the Air Force in the Post-INF world is bringing back forward-based, ground-launched cruise missiles which were explicitly banned in the INF Treaty, and the new version can be deployed by modifying the Navy’s current Tomahawk missiles. In addition to these conventional changes to the United States missile deployments, it is expected that the United States can focus on developing experimental technologies like “hypersonic weapons.” Hypersonic weapons are those that can fly at more than five times the speed of sound and would violate the technical restrictions within the INF Treaty. The US military without these treaty restrictions is likely to ramp up their research and development efforts and will put more focus on deploying these weapons systems in the field.
The decision to effectively end the INF Treaty by the United States ends an important era in International Relations and arms control. However, where one door closes, another door opens. The US decision to leave the treaty will have major consequences for international politics in the future as it likely will lead to a breakdown of US-Russian arms control cooperation, expansion of the US nuclear umbrella countering China in the Asia-Pacific region, and the development of conventional and exotic weapons systems that the US military will deploy.