The question is not whether Tony Blair has crossed his own “red line” on defence policy by agreeing to a Franco-German proposal for the establishment of an EU military planning unit independent of Nato. He clearly has. Neither is there any question that this new military alliance achieves the longstanding French goal of undermining Nato. It clearly does.

Mr Blair says that Nato will still have the right of first refusal on all missions. But his own officials admit, in the words of one who for obvious reasons prefers to remain anonymous: “The French won’t concede that Nato has the right of first refusal.” After all, Nato already employs more than 1,000 operational planners, according to Lord Robertson of Port Ellen, its Secretary-General; a new independent unit of some 30-40 planners can’t add much to planning capability — and can only exist to form the nucleus of a group that will grow and eventually displace Nato.

No amount of diplomatic fudge poured over the agreement can sweeten the bitter taste of those, this writer included, who believed Mr Blair meant “never” when he said that he would “never” cede control of British defence policy to the EU.

And it doesn’t take an excessively vivid imagination to conjure up George W. Bush’s reaction. This President, who values loyalty and straight talk above all else, undoubtedly vacillated between sadness and anger at the act of a Prime Minister who recently assured him, face to face, that he would never do anything to undermine Nato — a pledge it now appears was written in the sand.

All of this is obvious to even the most casual observer. Less obvious is the fact that Mr Blair has played into the hands of those neocons who are so influential in the Bush foreign policy establishment. Some 20 years ago, Irving Kristol, the godfather of the neo-conservative movement in America, contended that Nato had become irrelevant.

With the threat of Russian tanks rolling across Western Europe now sufficiently remote to make Messrs Chirac and Schröder feel more comfortable with Vladimir Putin than with George Bush, what conceivable American interest is served by devoting increasingly scarce resources to what was once called the defence of Western Europe? So ask a group of neocons, not for the first time paying tribute to Kristol’s prescience. Answer comes there none.

And now they have an additional reason to offer the President for quietly welcoming the formation of the new EU military unit — if a unit with no effective fighting force can be called “military” in any sense of the word — to replace Nato. America needs the “assets” which are now devoted to Nato — assets on which the new three EU Musketeers would like to call when the spirit moves them — to implement the President’s vision of a Middle East built around the institutions of democracy and free markets. Where better to find those resources than in the military bases and planning rooms that now constitute Nato?

Of course, the hunt for men, materiel and money to support the President’s policy need not stop in Europe. At a series of meetings with leading Australian businessmen and government officials, I was surprised to hear a uniform refrain: “Get your American troops out of South Korea.” These are not peaceniks; indeed, they are eager for the US to continue projecting power in the Pacific region.

But they see a possible conflict with North Korea as one that will be settled in the air, not on land. They hold the view that the 30,000 American troops stationed in South Korea are more of a liability than an asset. Inevitably, there will be incidents — rapes are the ones they most fear. These incidents will lead a new generation, for whom the last war on the peninsula is a distant or non-existent memory, to demand the departure of US forces. And depart they will, leaving a vacuum and ill feeling.

That, worry our Australian friends — and friends they are, having fought alongside America in six wars in the 20th and 21st centuries — will trigger a nuclear arms race in the region. With the American umbrella furled, Taiwan would surely want nuclear weapons to protect itself from forceful absorption by China; South Korea would realise just how exposed it had become to the will of a dictator madder than any now operating in the world, and would also want nuclear weapons.

Better, say the Australians, to remove ground troops before the rancour sets in and retain a presence by the judicious use of naval manoeuvres and other demonstrations that the Pacific still matters to the United States. The American umbrella would remain, but made of different stuff.

Top-level US defence officials are listening. And they are beginning to consider just how much less stretched their forces would be if withdrawal from Korean and Nato obligations could be arranged. In their view, Mr Blair has done them a great favour.

The Defence Secretary, Donald Rumsfeld, may already have signed on to the notion that the new UK-Franco-German arrangement provides the excuse for which he has been searching to redeploy Nato assets. Which would explain why, after an initially angry and decidedly hostile reaction to plans for the new tri-national military headquarters, he now professes himself “confident that things will sort themselves right”.

Nato made a great contribution to world peace, protecting Europe from the Soviets so that it could choose a new, peaceful future. Nato’s mission has been accomplished. But a reason for winding it down has, until now, proved difficult to come by.

By making it clear that America’s staunchest European ally has signed up to France’s “Yankee go home” policy, Mr Blair has made it unnecessary for the US to wield the dagger to kill a once-useful alliance. He has done it for America. And many with influence in the Bush Administration are discreetly applauding.

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