THE INTERMEDIATE-RANGE NUCLEAR FORCES TREATY (INF) has been a pillar of arms control for over 30 years. But in recent years it has been crumbling. On October 20th President Donald Trump announced that he intended to withdraw America from the treaty and build up missiles until Russia, believed to be cheating on the pact, and China, which never signed it, “came to their senses”. On February 1st he pulled the plug, after Russia failed to meet a deadline to come into compliance with the treaty. Even before American withdrawal takes effect in six months, the ripples are likely to be felt from Europe to Asia.
The INF treaty has its origins in the Euromissile crisis of the late 1970s and early 1980s. The Soviet Union’s deployment of the SS-20, an advanced and accurate missile that could strike most of Europe from deep within Russia, alarmed Europe. America had short-range missiles in Europe, which could not reach Soviet territory, and long-range ones at home and aboard submarines, but nothing in this middle category. If the Soviets attacked Europe with the SS-20, America would be forced to escalate to its biggest weapons. European allies fretted that it would not do so.
To assuage these concerns, and to force the Soviet Union to change course, America deployed the Pershing II ballistic missile and a new ground-launched cruise missile into Europe. That, in turn, worried the Soviet Union. These could reach Moscow in under ten minutes, potentially forcing leaders into a panicky response. Anti-nuclear protests roiled Europe as the new weapons rolled in.
The INF treaty cut through this knot. It prohibited not only the offending Soviet and American missiles but also the flight-testing, development and deployment of all ground-based missiles—both nuclear and conventional— with ranges between 300 and 3,300 miles. Almost 3,000 existing weapons were destroyed, with the Soviet Union getting rid of twice as many.
Why has the agreement now snapped? The most important reason is Russian cheating. America and its NATO allies accuse Russia of flight-testing, and then deploying, an INF-range cruise missile called the 9M729. Russia displayed the missile at a military theme-park outside Moscow on January 23rd, without convincing anyone of its bona fides.
Another nail in the pact’s coffin was China. In the 2000s Vladimir Putin toyed with the idea of leaving the deal as other states, including a rising China, whose relationship with Russia remained testy, were racking up non-nuclear intermediate-range missiles. As ties between Russia and China warmed, these concerns faded. It became America’s turn to worry that China was accumulating missiles beyond the treaty’s grasp, while America had to put its own aboard expensive and scarce ships, submarines and aircraft. Many in the Pentagon see a golden opportunity to redress the missile balance in Asia.
Should the treaty collapse in the summer, as now seems likely, there would be several consequences. Russia might build up intermediate-range missiles aimed at Europe. These could include not only the 9M729, but also the RS-26 “Rubezh”, an intercontinental ballistic missile that has been tested at ranges near the upper limit of the INF. Hence NATO’s warning on February 1st of “significant risks to Euro-Atlantic security”. In turn, America would speed up its pursuit of a matching capability. Officials admit that research is in the “early stages”; a working missile is at least a year away. Any missile race might also spell trouble for the New START treaty, a US-Russian arms-control deal that covers mostly longer-range weapons, due to be renewed in 2021.
If such missiles do materialise, putting them anywhere useful will require virtuoso diplomacy. European leaders would shy away from accepting them, perhaps more so after Mr Putin’s threat on October 24th that hosts “would expose their territory to the threat of a possible retaliatory strike”. If America were to cut a deal with one or two more enthusiastic allies, like Poland, over NATO’s head, it would shake the alliance. A major summit is due in March, ahead of the organisation’s 70th birthday in April. It is less clear how Asian allies would respond. Japanese diplomats are cagey. South Korea’s dovish government is unlikely to play ball. Guam, a heavily forested island, might be the likeliest option, though its distance from China might count against it.