The US-Russia spat over Edward Snowden, who exposed the US secret surveillance program, is just the tip of the iceberg amid a chilly relationship between the two nations, US experts said.

Russia recently granted Snowden asylum after he leaked classified information of a massive US surveillance program, to the irritation of Washington.

In retaliation, US President Barack Obama canceled next month's summit with Russian President Vladimir Putin, citing little progress expected on key issues between the two nations.

Minor issue in broader trend

US experts said the Snowden affair is a minor issue amid a broader trend of souring US-Russia relations.

Steven Pifer, a senior fellow at the think tank Brookings Institution, told Xinhua that the US-Russia relationship "is in a rough patch now," while cautioning against billing it as post-Cold War low point.

While the two sides have agreed on a broad range of issues including the Korean Peninsula, Iran and nuclear weapons reductions, the past 18 months or so have seen sharp differences over war-ravaged Syria, Pifer said.

Russia continues to support Syrian President Bashar al-Assad while the Obama administration has repeatedly called on the embattled leader to step down, causing a strain in the relationship.

Washington has also voiced concern over what it views as heavy-handed Russian domestic policies since Putin's return to the presidency last year, noted Pifer.

Speaking Tuesday on The Tonight Show with Jay Leno, Obama expressed disappointment over Russia's new anti-gay law.

At the same time, Putin believes painting the US as an adversary benefits him domestically as he reaches out to more conservative elements to maintain his base after losing middle class support in Moscow and St. Petersburg, Pifer said.

On Friday, US Secretary of State John Kerry said the US and Russia needed to better cooperate on issues such as Syria as he and Defense Secretary Chuck Hagel hosted Russian counterparts Sergei Lavrov and Sergei Shoigu in high-level talks (2+2 meeting) on security and strategy.

Snowden issue overblown

Pifer argued that Obama mishandled the Snowden case, allowing it to assume an inflated level of importance in the relationship. For decades, Washington and Moscow have been adept at containing such issues so as not to undermine the broader relationship.

"I think this administration got off on the wrong foot by asking for Snowden's return, when they had to know there was no chance the Russians would return him," he said.

Pifer added that the US would never have handed over a Russian defector if the tables were turned.

"(The US) unwisely made Snowden a bigger public issue than it should have been," Pifer said.

But he believed the summit was canceled because there was no prospect for progress on bigger issues.

"The impression out there, which is incorrect, is that it was canceled because of Snowden," he said.

In a briefing following Friday's 2+2 meeting, which was resumed after five years, a senior US official said that the two sides held "positive and constructive" meetings on a range of issues including Syria, Afghanistan, Iran and the Korean Peninsula, and the Snowden issue "did not dominate or overshadow the agenda."

Post cold-war strategy

Russia in recent years has moved to re-assert its influence in the post-Soviet space, including countries such as the Ukraine, Belarus and Moldova, although the Kremlin is not trying to rebuild the Soviet Union, Pifer said.

George Friedman, CEO of private intelligence firm Stratfor, argued that Russia is simply reacting to the 1991 massive reversal that, from his prospective, the US took every opportunity to exploit, from Kosovo to Ukraine and to the Baltics.

"For a while it appeared that the Americans would succeed in breaking Russian power permanently. If not for 9/11 they might have. Russia sees itself as creating a sphere of security to protect itself and assert its interests as a great power," Friedman said in an article on Stratfor's website.