Mr. Putin suggested then that Russia was rethinking the treaty, because other countries like North Korea, South Korea, India, Iran and Pakistan, as he claimed, possessed missiles banned by the treaty but were not party to it. “It is obvious that in these conditions we must think about ensuring our own security,” he said. A day later, Russia’s defense minister, Sergei Ivanov, called the I.N.F. Treaty a “relic of the Cold War” that “will not last forever.” The same month, Gen. Yuri Baluyevsky, chief of Russia’s General Staff, asserted that a party to the treaty could withdraw “if it provides convincing evidence that it is necessary to do so,” adding “we have such evidence at present.” That same year, Russia unsuccessfully sought a “global” I.N.F. Treaty that all countries would be party to, and submitted a formal proposal to the 2008 Conference on Disarmament.

Russian sentiment coincided with discussions held with senior Bush administration officials. Former Secretary of Defense Robert Gates wrote in his memoir that in his first meeting with then-Minister Ivanov, the minister stated that Russia wanted to withdraw from the treaty.

Despite Russia’s feelers, starting in 2004, about scuttling its international obligations, the United States has remained committed to the I.N.F. Treaty across three presidential administrations, valuing the treaty’s contributions to international security. For over five years, in more than 30 discussions and six experts’ meetings, the United States tried without success to engage Russia in a productive dialogue on its violations of the treaty. Still, Russia continues to deny it is in violation and instead disingenuously claims that the United States is independently seeking to leave the treaty.

Nothing could be further from the truth.

What is true is this: Starting over a decade ago, and having failed to mutually end or globalize the I.N.F. Treaty, Russia decided to start covert development of a system that would violate the treaty. By now, it has developed and deployed missiles with the capacity to strike targets within the treaty’s distance limits and threaten locations in Europe and Asia.

I have seen the argument that the end of the I.N.F. Treaty is the beginning of a new arms race, and that it is better to have a treaty with Russia than nothing at all. Let me be very clear: A treaty cannot exist when one side complies and the other does not. And we are not talking about a handful of violating missiles. Russia has already fielded several battalions of 9M729 missiles.