Consider Joschka Fischer. He is the one-time leftwing street fighter who wears a grey suit. He is that rare German politician who communicates with the world by personal e-mails, instead of cowering behind his press spokesman. He is the former pacifist who deployed troops in Afghanistan. He is the foreign minister who breaks the mould, the coolest of that coolest of generations, the 68ers.

In short, Mr Fischer feels irresistible. So when he arrives at America's door bearing a large bouquet of apologies, as he did last week, he expects success. Sure, the US and Germany are now locked in a dispute over Iraq. America wants to invade Iraq; Mr Fischer and his senior coalition partner, Gerhard Schroeder, want no part of the story. And sure, the Red-Green coalition thumbed its nose at the US in its moment of great need, just so it could get re-elected.

But, after all, America, like Germany, is a democracy. The US ought to understand about the weird necessities of election campaigns. So, runs the Berlin line, let us treat the dispute like the family quarrel it was, and patch things up. Berlin deserves a little understanding. For who is doing the US the favour of taking over that unenviable baby-sitting job called Afghanistan? Germany.

But Mr Fischer turned out not to be irresistible in Washington. The White House door stayed shut, as did its side entrance to the National Security Council. Congress? Nobody there - they were back at home campaigning. Mr Fischer did get to meet his counterpart, Colin Powell, the secretary of state. But it is clear that, for Team Bush, the "poisoned" relationship is still poisoned, no matter how charming the representative from the other side. Mr Fischer had to make his case - humiliation of humiliations! - via the media.

For each of the arguments Berlin has been making to those closed doors, there is a counter-argument. First, the Germans argue it was not worth trying to sell war on Iraq in Germany since the voters would not have gone along. If the Schroeder government had made the case for Iraq, it would have lost the election. Extreme rightwing groups would have picked up the slack, as happened when Lionel Jospin, France's former socialist prime minister, foundered in his country's general election campaign.

Well, yes, the German population is understandably war-averse. But who are Germany's leaders? Messrs Schroeder and Fischer. Their ambivalence was clear to voters; hence voter negativity. Things might have been different had the Red-Green coalition made a strong case.

Second, the German government believes the US has not thought sufficiently about what comes after Saddam Hussein in Iraq. Supposing the invasion goes well; then what? As long as things are so unclear, Germany says, its position is ohne mich - "without me". That may be true - but what is the alternative? Iraq could deploy atomic, biological or chemical weapons in the near future. So regime change, at least regime change that comes fast, may prevent disaster.

There is another reason for Germany to engage. The US does not have a ready map for the post-Iraq Middle East. But is that not an argument for Germany to ally itself with the US now? To partake of the chance to reshape the Middle East, Germany has to prove itself a good US partner early on. To the victors go the policy spoils.

Mr Fischer, of all people, should understand this. For years, he has tried to build up Germany's role in world affairs. A while back, there was a "Fischer plan" for Israel and the Palestinians; in the past week, he has mooted another plan to the US Anti Defamation League. To stick with containment is very much the old style of Hans-Dietrich Genscher, the former foreign minister. And Genscher was no 68er.

Last, Germans tend to argue that action against Iraq could enrage Muslims throughout the world and embolden Islamic fundamentalists. They say the German voter is willing to play a part in the war on terror but believes action in Iraq would undermine it. But nothing emboldens fundamentalists and thugs more than a show of weakness or division among their opponents. And the Red-Green coalition has already provided that with its top-decibel, get-that-vote rejection of the US programme.

What is more, say the US does succeed in setting Iraq on the path of democracy. This will halt the Middle East's vicious cycle. Iran, Syria, and Libya will see the consequences of underestimating the US. They will back down. And their own people will be inspired by the hope for democracy.

Of all the German politicians in power, Mr Fischer is in his way the most pro-American: he is what Gary Smith of the American Academy in Berlin calls a "born-again" Atlanticist. So this is his opportunity. But his arguments do not translate across the Atlantic, as they stand at the moment. If Germany's foreign minister wants to carry influence with the US administration, perhaps he should find a new approach in time for this month's Nato summit in Prague.

© Copyright 2002 Financial Times