Cold war tensions linger

But reminders of past tensions between the two former Cold War foes are never far from the surface.

News this month that the head of Moscow's deep-cover spying operations defected after betraying the network in June was a humiliating setback that spurred cloak-and-dagger headlines around the world.

The extradition of Bout, who was arrested in Bangkok in March 2008 in a US-led sting operation, was another unhappy surprise for Moscow, which had warned repeatedly that his case was politically motivated and could damage US-Russia ties.

An inspiration for the Hollywood movie "Lord of War" starring Nicholas Cage, Bout faces US accusations of trafficking arms since the 1990s to dictators and conflict zones in Africa, South America and the Middle East.

Samuel Charap, a Russia expert at the Center for American Progress, a liberal think tank, said Washington's determination to bring Bout to trial may sow fresh doubts about the United States' commitment to the broader reset policy.

A bigger worry, however, is continued Senate delay on START, which Obama and Medevedev signed in April, committing to cut deployed nuclear warheads by about 30 percent.

"START is the cornerstone, and it is a demonstration to the Russians on whether Obama can deliver, and whether the US is really interested in pursuing shared interests cooperatively," Charap said.

While both Obama and Secretary of State Hillary Clinton have urged the Senate to ratify the measure during its "lame duck" session in coming weeks, those hopes were hit hard on Tuesday when a key Republican said that did not leave enough time to debate.

The comments by Senator John Kyl, the number two Republican in the Senate, could push a START vote to next year, when passage may be more difficult because Democrats emerged with a smaller Senate majority following recent elections.

"It is going to be a real test of the president's political capital in Washington to get (START) done," said Conley of CSIS. "The question will be: does the president have the ability to move his foreign policy agenda forward."