This is still a war that has few clear enemies and still fewer clear aims

"Phoney war" is a phrase that has been employed a good deal recently. Perhaps the French equivalent from 1940, la drôle de guerre, "the strange war", is more appropriate. For it is quite extraordinarily strange – given the emotions naturally stimulated by the atrocities of two weeks ago – that America has still not fired a single bullet in response to the outrages.

"Phoney war" is a phrase that has been employed a good deal recently. Perhaps the French equivalent from 1940, la drôle de guerre, "the strange war", is more appropriate. For it is quite extraordinarily strange – given the emotions naturally stimulated by the atrocities of two weeks ago – that America has still not fired a single bullet in response to the outrages.

The world should be thankful that the Bush administration did not react with immediate violence, but instead followed its better instincts and proceeded with caution. The Vice-President, Dick Cheney, the Secretary of State, Colin Powell, and the Defence Secretary, Donald Rumsfeld, have literally been through the wars – Vietnam and the Gulf conflict – and know that the last thing America needs is a war she cannot win and that has no clear aims. Indeed it is difficult to see what America can do. Any military move runs the risk of being ineffective against fanatical terrorists for whom, as we have seen, death holds few horrors and who would not think twice about retaliating in kind, while alienating wider Arab and Muslim opinion. Hence the delayed military response, hence the increasingly careful diplomatic offensive and hence, most hopefully, the administration's pressure on Israel and the Palestinians to reduce tensions.

Which is not to say that there are not some differences within the war cabinet. Mr Powell, for example, has proved to be much more doveish than the defence team. When the Secretary of State ponders aloud on the possibility of allowing the Taliban to remain in power if Osama bin Laden is captured, he sounds significantly less hawkish than the Deputy Defence Secretary, Paul Wolfowitz.

That said, however, even Mr Rumsfeld himself is, sensibly, talking in strangely Clare Short-like terms about the number of people who are starving in Afghanistan and the humanitarian crisis that has already hit that benighted country. So we should not exaggerate the differences within the Bush team.

We may be unpleasantly surprised, but all the indications are that there will be no prolonged conventional ground war in Afghanistan; that there will be no "carpet bombing" of innocent Afghans and that little force will be used beyond the minimum necessary to apprehend Mr bin Laden and his most important collaborators. That is a relief, because nothing would be more guaranteed to generate scores of new bin Ladens than the sort of action urged on Mr Bush in the first days of the crisis.

But if America's war aims have narrowed, they are not very much clearer than they were when Mr Bush first declared his war on terrorism. This lack of clarity will have to be remedied if Mr Bush does not want to see the tiny fissures that are emerging in his grand coalition widening into more dangerous splits. We have for example, the slightly odd situation of Mr Blair sounding more hawkish than the President. We hear, more understandably, that the Pakistanis are worried about some of the administrations' demands; and we know some of our European partners are wary about an "adventure", as the German Chancellor, Gerhard Schröder, called it. Not to mention the stresses that arise when attempts are made to persuade Iran and Israel to become allies.

The need for a clear set of war aims is becoming urgent as we edge closer to military action. What is the purpose of such action in Afghanistan? Which countries are officially regarded as "harbouring" terrorists? What demands will be placed upon them?Are we now going to depose Saddam Hussein? And where is the solid evidence that links Mr bin Laden to the atrocities? Mr Bush must not turn this strange, phoney war into a real one until he can say what it is for.