LONDON -- As British Prime Minister Tony Blair passes his 50th birthday, the almost boyish bounce that characterized him in the years when he got to the top of the Labour Party, reformed it and then won two crushing general election victories has been replaced by a more careworn appearance. This may seem surprising given the convincing military victory that British forces scored in Iraq as junior partner to the Americans. The days of early spring -- when Blair appeared to risk a defeat in Parliament that, he has subsequently stated, would have led him to resign -- seem far away.

An opinion survey published at the end of April showed that almost three-quarters of those polled named the United States as Britain's most reliable ally; 55 percent picked France, with which the prime minister has been at odds, as the single least reliable ally.

Nevertheless, his position at home and abroad is more fragile than might appear. His ambitions to take his country more firmly into Europe face a continuing deep split with France, which goes well beyond the immediate differences over Iraq. In late April, an attempt to build a bridge with Russia fell flat. At a joint press conference at the end of a visit by Blair, Russian President Vladimir Putin insisted on the need for United Nations weapons inspectors to return to Iraq and made a mocking reference to the failure of coalition forces to find weapons of mass destruction.