For the United States, this special relationship with Britain has downgraded in its global strategy, which focuses more on relations with China, India and Russia. For Britain, the long-term "pro-U.S." policy has weakened its influence in the world.

U.S. President Barack Obama (R) and visiting British Prime Minister David Cameron attend a joint press conference after their meeting at the East Room of the White House in Washington D.C., capital of the United States, July 20, 2010. [Zhang Jun/Xinhua]

Obama, during his Asian tour last November, claimed that he was the first "Pacific President" in the U.S. history, while Cameron has voiced his ambition on rebalancing the special relationship with Washington, also saying "Britain should never be frightened of saying no to America."

However, in most circumstances, relations among countries are decided by national interests and security, not by leaders' emotion.

For Washington and London, to rebalance their special relationship does not necessarily mean that the ties would be ignored by each other.

Decision makers in Washington have to see the following two points -- first, as one of the UN Security Council permanent members with "power of veto," Britain has not uttered the "second voice" on the issues concerning U.S. interests and security; and second, Britain has also contributed a lot in Iraq and Afghanistan.

On the grand chessboard of U.S. geopolitical strategy, Washington expects Britain to continue to be a key chessman for serving U.S. strategic interests in Europe. Obviously, a "United Europe," possible in the continent, would challenge U.S. dominance on the international arena.

As Obama said after his meeting with Cameron, "The United States and the United Kingdom enjoy a truly special relationship ... The United States has no closer ally and no stronger partner than Great Britain."

It is a heartfelt statement on the bilateral ties between the two countries.

Cameron and his coalition government have to realize that London's influence on the international arena would continue being limited by Washington, if its position in the special relationship could not be upgraded from "subordinate" to an "equal" partner.

Yet, for Britain, the upgrading journey is quite long.