The terms of the Intermediate-Range Nuclear Forces [INF] treaty, which was signed amid great fanfare in 1987 by Mikhail Gorbachev and Ronald Reagan and banned an entire class of medium-range nuclear missiles, are still very much in effect. Experts say the charge that Russia is violating the treaty, or at least trying to circumvent it, is fraught with negative symbolism that is not helpful for US-Russia relations that have already hit their post-cold-war nadir for a wide variety of reasons.
"This is a bad sign. It is technically easy to violate that treaty, and so if someone wants to make an issue out of it, it will become an issue," says Alexander Konovalov, an arms control expert and president of the independent Institute of Strategic Assessments in Moscow.
"But so far all talk of violations reflect minor technical matters that could be quickly solved, if there were political will to do so. This is basically about the political environment, and not some serious problem in the military sphere," he says.
The Obama administration has not filed a formal complaint with the Russians. But according to several news agencies, US officials this week briefed their NATO counterparts about the alleged Russian "breakout" weapon, which some reports say is a hypersonic cruise missile known as the R-500 Iskander-K.
That would be an upgraded version of the Iskander series of short-range missiles, which Russia has already threatened to station in its westernmost region of Kaliningrad to counter NATO's planned missile-defense systems. With slight engine modifications, the Iskander-K could be capable of striking targets almost anywhere in Europe, experts say.
After the R-500 was first tested in 2007, Russia's then-Defense Minister Sergei Ivanov bragged about the new weapon's "surgical" accuracy and complained to the State Duma that the INF treaty was an outdated agreement that favored the US and perhaps should be abolished. "The treaty is simply a cold war vestige and we are concerned," he said.
As recently as last summer, Mr. Ivanov, now Kremlin chief of staff, publicly questioned the value of the INF treaty for his country, since Russia faces many potential threats on its borders and the US does not.
"The Americans have no need for this class of weapon, they didn’t need it before and they don’t need it now," the state-run RIA-Novosti agency quoted Ivanov as saying. "They could theoretically only attack Mexico and Canada with them, because their effective radius doesn’t extend to Europe."
Other news reports focus on the RS-26 Rubezh [Frontier], a new "medium class" intercontinental missile being developed as part of a broad Putin-era modernization of Russia's nuclear forces. Some US sources claim the Rubezh is being tested in both a treaty-compliant long-range version and an INF-violating medium range version.
The Russians insist the new missile, which is still in the experimental stage, is an intercontinental missile and therefore should be counted under the terms of the New START strategic arms reduction accord negotiated during Mr. Obama's first term.
The key problem, experts say, is that Russia is in the midst of developing a wide range of new nuclear-capable weapons to replace its aging Soviet-era arsenal, and in an atmosphere of growing mistrust between Moscow and Washington, almost any small misunderstanding can become a big controversy.
"I see no good reason for the Americans to raise this now," says Andrei Klimov, deputy chair of the State Duma's international affairs committee.
"Lord knows, there are plenty of international issues that need our attention, such as Syria. Maybe someone in the US is trying to score political points, or distract public opinion. It does seem like domestic politics is the priority [for political forces] in the US just now," he says.
Mr. Konovalov says that Russian war planners learned their lesson in the 1980s, after they modernized Soviet medium-range nuclear forces in Europe by replacing old missiles with the new SS-20, a mobile missile that carried three independently-targeted warheads, which lowered most of western Europe's warning of impending nuclear attack to barely 15 minutes.
"The Europeans asked the Americans to respond, so they deployed their own medium-range missile, the Pershing-II in Europe, which lowered our own warning threshold very sharply, to about 12 minutes in Moscow. In other words, the upshot was that our strategic position deteriorated sharply. Why would we want to do that again?" he says.
Vladimir Dvorking, a leading Russian arms control specialist with the official Institute of World Economy and International Relations in Moscow, says any discussion about INF treaty violations is premature at best.
"This might have something to do with all the tests going on in Russia's missile complex," he says. "But there is no final picture of how these new missiles will look, or how they will be used once they are deployed. From time to time people remember the INF treaty, as Sergei Ivanov did recently, and suggest that Russia should withdraw from it. I believe that's a big mistake."