By Steven Rosenberg BBC correspondent in Russia

As United States Secretary of State Colin Powell visits Moscow for talks with the Russian president, BBC correspondent Steven Rosenberg looks at how relations between the two countries, although strained, may still thaw over the war on terror.

At Moscow's Wedding Palace Number Four, the band strikes up, the doors swing open - and in march the bride and groom.

There had been talk of a new partnership, of burying the Cold War hatchet

Michael is American and in a tuxedo. Inna is Russian, and in a flowing white dress.

Despite all the differences in language and culture, they are certain they will be able to make this relationship work.

"We believe," Michael told me after the ceremony, "that no matter from which country a person's from, people from all over the globe can actually get along and learn to love one another and put away their differences".

Smiles then squabbles

Not so long ago it seemed that Vladimir Putin and George W Bush had buried their differences.

We've always known that it wasn't going to be a straight line process of moving from adversaries to allies Alexander Vershbow, US Moscow ambassador

Their friendship seemed to blossom after 11 September - when Moscow became Washington's ally in the war on terror.

There was talk of a new partnership, of burying the Cold War once and for all.

But behind all the smiles, there were squabbles - and then a major falling out.

The war on Iraq came between Russia and America.

Washington accused Moscow of arming Saddam Hussein, and Moscow in turn slammed Washington for breaking international law.

New realism

The honeymoon was over.

Events such as the recent Saudi bombing may make the two countries work together

"I think that there's a bit more realism," Alexander Vershbow, US Ambassador to Moscow told me.

"There may have been a sort of honeymoon atmosphere as the Putin-Bush relationship got off to a flying start and we had very successful summit meetings, and certainly good personal rapport."

"But we've always known that it wasn't going to be a straight line process of moving from adversaries to allies."

There is more realism on the Russian side too. And a feeling that Russia has too little to show from its friendship with America.

"The United States presented us with a fait accompli by withdrawing from the ABM treaty," complained Sergei Rogov, an adviser to the Russian Security Council.

"Russian-American trade is not growing, US investment in Russia is not growing, in fact more money is coming from Russia to the United States than the other way around.

"What about the terms of Russian membership of the WTO [World Trade Organisation]? There have been no concessions by the United States as Russian admission goes."

War on terror

America here is seen as having gained much more: US bases in Central Asia, right on Russia's doorstep; Nato's enlargement up to Russia's borders.

And - what hurts most of all - the ability to ignore Moscow's opinion.

"There are some people in the United States," Mr Rogov believes, "who would like to finish Russia, so Russia would never again be a player which could complicate American geo-political strategy".

"And there are some people in the Bush administration who always were not just anti-Soviet, but anti-Russian."

But, like after 11 September, it is the war on terror which may still re-unite Russia and America.

This week's suicide bomb attacks, first in Chechnya, then in Saudi Arabia, may well serve as a reminder of just why Moscow and Washington had pledged to work together.