INF Treaty
The 1987 agreement that abolished an entire class of nuclear weapons, verified by inspectors living at each other's factories, and that the United States quit in 2019.
On December 8, 1987, Ronald Reagan and Mikhail Gorbachev signed a treaty that did something no arms control agreement had done before: it did not cap a weapon, it abolished one. Every ground-launched ballistic and cruise missile with a range between 500 and 5,500 kilometers, deployed or not, was to be destroyed. By the deadline in May 1991 the two sides had eliminated 2,692 missiles, 1,846 Soviet and 846 American, along with their launchers and support equipment.
Why this class of weapon
The trouble began with the Soviet SS-20, deployed from 1976. It was mobile, accurate, carried three warheads, and could reach any target in Western Europe in under ten minutes. It did not threaten the United States, and that was exactly the problem. NATO's defense rested on the promise that an attack on Hamburg was an attack on Chicago. A weapon that could destroy European targets without touching America invited Europeans to wonder whether Washington would really trade its own cities for theirs.
NATO's answer in December 1979 was the double-track decision: negotiate for removal, and if that failed, deploy American Pershing II ballistic missiles and Gryphon ground-launched cruise missiles in Europe from 1983. The Pershing II was the mirror image of the Soviet problem, a fast, accurate weapon that could reach Moscow in roughly ten minutes, and Soviet planners hated it for the same reason NATO hated the SS-20.
The deployments produced the largest peace demonstrations in European history and some of the most dangerous years of the Cold War, including the 1983 Able Archer exercise that parts of the Soviet leadership appear to have read as cover for a real attack. Both sides had built a weapons class that made everyone less safe and nobody stronger.
What made it work
Reagan had proposed the zero option, remove all of them, in 1981, and it was widely treated as a negotiating position designed to be rejected. Gorbachev accepted it. The near-miss at Reykjavik in 1986, where the two men came close to agreeing to abolish far more than this, cleared the ground.
The verification regime was the real innovation. The treaty allowed short-notice on-site inspections and put permanent monitoring teams outside each other's missile plants, at Votkinsk in Russia and Magna, Utah. American inspectors watched Soviet railcars leave a Soviet factory for thirteen years. That arrangement, more than the missile numbers, is what later agreements were built on.
How it died
From 2014 the United States accused Russia of testing and then deploying the 9M729 missile at prohibited ranges. Russia denied it and countered that American missile defense launchers installed in Romania and Poland could fire offensive weapons. Neither side moved. Washington announced withdrawal in February 2019 and completed it on August 2, 2019.
The unspoken reason was in Asia. China was never a party, and had spent two decades building the world's largest intermediate-range missile force precisely because nothing stopped it. American officials increasingly viewed a treaty that bound Washington and Moscow, and left Beijing free, as a self-imposed handicap in the theater that mattered most.
The echo
The class is coming back. The United States has begun rotating its Typhon mid-range launchers through the Pacific, and Russia has used its intermediate-range Oreshnik against Ukraine. Europe is again debating hosting American missiles, with the same arguments as 1979 and less public patience.
The INF Treaty is the cleanest evidence that nuclear arms control can genuinely work: an entire category of weapons was invented, deployed, feared, and then removed, with inspectors to prove it. It is also evidence of what such treaties require, which is two parties who both consider the weapon a liability. In a world with three consequential nuclear powers rather than two, that condition is much harder to meet.