The departure of Karl Rove from the White House leaves the fate of the Bush presidency largely in the hands of General David Petraeus. If the counterinsurgency strategy he has successfully pioneered in Anbar province can be replicated in Baghdad, then victory in Iraq can still be snatched from the jaws of defeat in time to prevent American politics turning decisively against the Bush doctrine after next year’s presidential election.

The gravest danger to the survival of Western civilization, and Europe in particular, would be a concatenation of Islamist triumphalism and American isolationism. The primary goal of European statesmanship now should be to prevent the predominance of either of these pathologies. This requires Europeans to offer support to General Petraeus in Iraq, to shoulder more of the growing burden of the NATO campaign in Afghanistan, and to strengthen those who are resisting the tide of Islamism that is at present sweeping across the Middle East and the Indian subcontinent.

Are these, though, the priorities of all or indeed any of the European democracies? On the contrary: most of Europe is doing none of these things. While America has been building up its forces in Iraq, Britain — the only European country with a significant presence there — has scaled back its troops to the point where they are so beleaguered that they can barely protect themselves against the Shia militias. The Iranian Revolutionary Guards are not only training and supplying, but also directing their proxies in Basra, the most important port in the Persian Gulf, which Iran has long coveted.

On Monday the New York Times criticized Gordon Brown’s government for “taking the wrong way out of Iraq” by “reaping domestic political credit for withdrawal without acknowledging that the mission has failed.” Well, no government ever likes to admit defeat, but Mr. Brown has certainly not given the Bush-Petraeus strategy the slightest support. The danger is that a precipitate British exit strategy will leave American forces dangerously exposed.

Meanwhile, the rest of the European Union is not only doing nothing to bolster the Iraqi government, but is turning a blind eye to Al Qaeda’s clear policy of exterminating religious minorities in Iraq, as the horrific attacks on the Kurdish Yazidi sect this week demonstrate.

As for Afghanistan: there, too, the Europeans are not pulling their weight — with the exception of the British, who are taking heavy casualties in intense fighting to prevent the Taliban from seizing control of the southern province of Helmand. The death last Saturday of Captain David Hicks, who continued to lead his company in battle even after he was mortally wounded by rocket and mortar fire, is typical of the heroism of the young officers in action there. Many of them by now have more combat experience than the generals who lead them.

Like the “lions led by donkeys” of World War I, they are angry with their superiors at home who expect them to work miracles with inadequate numbers and equipment. They respect their American comrades, but feel nothing but pity and contempt for their European counterparts, who are not allowed to go near the action. My deepest concern, however, is about the likely consequences of Europe’s defeatist attitude toward the Islamist flood that is threatening both Israel and the moderate Muslim states. There are various pieces of evidence that, taken together, suggest that the policy of refusing to deal with Hamas will soon be quietly dropped, that Israel will be pressured to repudiate its strategy of punitive retaliation as used against Hezbollah a year ago, and that Europe is already replacing the Bush doctrine of pre-emptive war with a new doctrine: the pre-emptive cringe.

This week, for example, the House of Commons foreign affairs committee issued a report that castigated Tony Blair for refusing to join the European hue and cry against Israel during last year’s Lebanon crisis. The parliamentarians went on to demand that the Brown government should open negotiations with “moderate elements” in Hamas — and that Mr. Blair, in his new role as Middle East peace envoy, should do the same.

What lies behind such demands from the European foreign policy establishment? The truth is that semi-official talks with Hamas are already happening, facilitated by shadowy figures such as Alastair Crooke, a former British intelligence officer who now runs an EU-funded outfit, Conflicts Forum, which lobbies on behalf of Hamas, the Muslim Brotherhood, Hezbollah, and other Islamist organizations to promote their image as “moderates” with whom the West can do business. Mr. Crooke has close connections with Javier Solana, the former secretary general of NATO, now the de facto EU foreign minister. One of the most powerful recruits to the cause of making Hamas respectable is the BBC, which has been promoting the “moderate Hamas” line even more assiduously since Hamas claimed to have negotiated the release of its kidnapped Gaza correspondent Alan Johnston. This kidnap, by a terrorist gang calling itself the “Army of Islam,” was given global saturation coverage for months, but as Melanie Phillips showed in the Spectator magazine, there is good reason to believe that the kidnappers and Hamas were really working hand in glove.

Just as America’s pre-emptive strike against Iraq set off a benign, though short-lived, domino effect across the Middle East, so Europe’s pre-emptive cringe could precipitate a malign domino effect, with pro-Western states such as Egypt, Jordan, and Pakistan falling into Islamist hands. It does not help those American presidential candidates threaten to break the embargo on talking to our sworn enemy, Hamas, while simultaneously bombing our ally, Pakistan. Faced with a jihad that may last for generations, the nations of the West can choose whether to hang together, or hang separately.