No one who has ever seriously believed in any cause finds it easy to criticize that same cause in public. The doubter's life can be hard, lonely and insecure. Conscience makes cowards of good people, around whom the habit of loyalty coils like a snake, difficult to shake off. In the battle between the heart and the head there is never an easy winner.

Tony Blair's belief in the importance of the US is a classic example of the perils of an undifferentiated loyalty. His own current problems need to be understood with that in mind. Some of his judgments over Iraq make sense, but are not necessarily excused by the fact that Blair is engaged in a struggle with realities which threaten one of his most enduring instincts.

Blair has long held the view that British domestic politics take place downstream from the US. He thinks Bill Clinton's election in 1992, and still more his re-election in 1996, were essential preconditions for Labour's own victory a few months later in 1997. He thought that the presence of a Democratic president in the White House made Labour appear to be cutting with the grain of history, not against it.

By the same yardstick, Blair saw George Bush's election in November 2000 as a more serious challenge to Labour than most people realize. It was one of the main reasons why he was so determined to be the first foreign visitor to Bush in early 2001. By getting to the president's shoulder at Camp David, Blair aimed to squash any pre-election attempt by William Hague to position the Conservatives as the party in touch with the new America. He is just as determined to prevent Iain Duncan Smith doing the same thing now.

Since 1997, Blair's belief in the importance of America has of course widened from domestic to international politics. He seems gradually to have formulated an approach to foreign policy which sees the US as the essential nation in the settlement of global and regional issues, and which identifies the Anglo-American relationship as the necessary catalyst ensuring American global engagement rather than isolationism.

Just how much he really believes in the mystique of the so-called "special relationship" is a hard call, especially given the more overwhelming evidence that Blair thinks of himself as a European. But he certainly acts the part of First Buddy with conviction.

No one who heard Blair speak at a White House dinner with Clinton in 1998 would be in much doubt where his heart as well as his head lay. That evening Blair quoted the biblical remarks of Harry Hopkins, Franklin Roosevelt's emissary to Churchill, at a wartime dinner in London: "Whither thou goest I will go, and whither thou lodgest I will lodge. Thy people shall be my people, and thy God my God. Even to the end."

Nearly two years into the Bush administration's term, it is easy to forget that Blair sometimes had to struggle to secure US international engagement under Clinton too, and over committing US forces in Kosovo in particular. But any problems which Blair encountered with Clinton are as nothing beside those he has faced with his successor. As Frances Fitzgerald writes in a compelling essay in the current issue of the New York Review of Books: "The Bush administration has clearly broken with the internationalist premises that have been accepted by every other administration since World War Two, with the exception of Reagan's first."

As Fitzgerald points out, George Bush has rarely defined the goals of his administration's foreign policy. In public, he has talked mainly in vague, general terms. Depending on his audience, as in his adjoining article today, there is more or less mention of allies. But in most Bush speeches, the world is a place of threats against which US-defined solutions offer the greatest security. It was summed up in Bush's election campaign comment about threats to America: "We're not so sure who the they are, but we know they're there."

One result is that no one, including America's allies and perhaps including Bush himself, has a very clear idea of the kind of world that Bush would really like to see beyond US shores. Perhaps he will rectify that omission when he addresses the UN today in New York. But the other result is that Bush's subordinates, led by Dick Cheney and Donald Rumsfeld, have repeatedly set the agenda in a series of steps which amount to a wholesale repudiation of any theory based on collective action and alliances.

The extreme version of this approach is summed up by the number three man at the State Department, John Bolton, who once proclaimed: "There is no such thing as the UN. There is an international community that can be led by the only real power left in the world, and that is the US, when it suits our interests and when we can get others to go along."

A parallel approach has recently allowed the Pentagon, which has systematically opposed, abrogated and binned a series of international treaties, to abandon its long-standing "threat-based strategy" in favor of a "capabilities-based approach". According to Defense Secretary Rumsfeld this means that America needs to build up its defenses on land, sea, air and space "to defend our nation against the unknown". As Fitzgerald points out: "For the overall Defense budget, a 'capabilities-based approach' means simply that the Pentagon can ask for whatever it wants without having to justify its requests by the existence of even a potential enemy."

This is the reality which constantly subverts Blair's attempts to portray the Bush administration as a willing partner in the new moral order that the prime minister advocated at Brighton last year. He was at it again this week, claiming to the TUC that in today's world "internationalism is practical statesmanship". Everywhere but in Washington, it should be added.

It is hard not to feel some sympathy with Blair's predicament. He believes in the right things. He is trying to exert an influence that needs to be exerted in pursuit of a good strategy that would make the world a safer and better place. Yet for all his efforts he gets only grief, in Washington and at home.

He gets grief because there is a profound disjunction between what he wants to believe about this administration and what is in fact the case. But this administration has trashed the rules that Blair wants to play by. Rather than face that reality head on, he pretends, in public at least, that it does not exist. It's the mistake that other loyalists in other causes have made down the years. Like them, Blair faces a choice between heart and head, and between loyalty and truth. Like them, he risks allowing excess loyalty and insufficient clarity to make the wrong call.

© Guardian Newspapers Limited 2002

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