By Paul Reynolds
World Affairs correspondent BBC News website
Putin in Munich: US has "overstepped its national borders"
Russian hostility to the American plan to station anti-ballistic missiles and their radar in Poland and the Czech Republic is an indication of the wider unease in relations between Moscow and Washington.
The issue also threatens repercussions in other areas of arms control, with Russia talking of pulling out of its 1987 treaty with the United States banning intermediate range nuclear forces (the INF treaty).
It shows that the effort to solve one problem, the potential threat to the United States from new generations of missiles from countries like North Korea and Iran, is producing a whole new set of diplomatic difficulties.
The result of the confrontation - reflected in other arenas such as trade and economics - is that problems that might have been and in some case actually were solved in the post Cold War euphoria are now producing echoes of the Cold War itself.
Conventional forces treaty
President Putin, in his annual speech to parliament on 26 April, broadened the Russian criticism of the West over defence by declaring that Russia was freezing and might end its commitments to force reductions under the Treaty on Conventional Weapons.
This treaty, originally signed in 1990, was modified in 1999 to take account of the break-up of the Soviet Union. Russia has ratified the modified version but the United States and other Nato countries are linking their ratification to the withdrawal of Russian forces from Moldova and Georgia, a linkage that Russia rejects.
Cold War-style linkage is back in the diplomatic armoury.
In a late effort to patch up their differences, the US Defence Secretary Robert Gates went to Moscow on Monday for what looked like unsuccessful talks with Mr Putin.
Later in the week, Nato foreign ministers will meet the Russian Foreign Minister Sergei Lavrov.
The Americans are hoping to base ten interceptor rockets in Poland with accompanying radar in the Czech Republic.
In the absence of a Nato agreement on this system, this is a bilateral matter between the US and the two Nato members.
The system is designed to intercept missiles that might fly over Europe on their way to the United States or be aimed at targets in Europe.
This is how the US Deputy Secretary of Defence Gordon England described the proposed system in a speech in March:
"This European site is about enhancing the defence of the homeland, and providing defences for our forward-deployed forces and our allies, especially against emerging threats from Iran and the Middle East."
"Unfortunately, leaders from the Russian Federation have expressed some reluctance - in remarkably strident language. The United States has been - and will continue to be - transparent with Moscow about missile defence plans.
"The facts should speak for themselves: the systems are not designed to counter - are not capable of countering - Russia's missile capabilities, and in addition, they include no offensive capabilities."
To try to placate the Russians, the Americans have offered them what Mr England called increased "missile defence cooperation-confidence-building measures like radar data-sharing, and joint missile defence testing."
This, so far at least, has not been enough for Russia. Even though technically the ten missiles in Poland could not have any effect on Russian rockets, Moscow sees the American plan not only as another encroachment of a Nato-related system on its doorstep but as another manifestation of US expansionism.
The Russian attitude was summed up in a strong speech made by President Putin at a conference in Munich in February, attended by Mr Gates.
"Today we are witnessing an almost uncontained hyper use of force - military force - in international relations, force that is plunging the world into an abyss of permanent conflicts," Mr Putin said.
"We are seeing a greater and greater disdain for the basic principles of international law. And independent legal norms are, as a matter of fact, coming increasingly closer to one state's legal system. One state and, of course, first and foremost the United States, has overstepped its national borders in every way.
"This is visible in the economic, political, cultural and educational policies it imposes on other nations. Well, who likes this? Who is happy about this? "
Mr Putin was careful to say that Russia would honour its obligations under strategic arms treaties, the most important of which will limit Russia and US to between 1700 and 2200 deployed warheads by the end of 2012.
However, he hinted that Russia was not happy at the restrictions imposed by the treaty on intermediate range missiles.
"Today many other countries have these missiles, including the Democratic People's Republic of Korea, the Republic of Korea, India, Iran, Pakistan and Israel. Many countries are working on these systems and plan to incorporate them as part of their weapons arsenals. And only the United States and Russia bear the responsibility to not create such weapons systems.
"It is obvious that in these conditions we must think about ensuring our own security."
Russian officials have suggested that if the American anti-missile deployment takes place in Eastern Europe, then Russia might withdraw from the INF treaty.
This sounds to US and Nato officials as an excuse not a reason.
But such linkage is part of the new reality of international relations.