One moment last week epitomised the current quandary of American neoconservatism. During the latest bout of conflict in the Middle East, Iraq’s prime minister Nouri al-Maliki issued the following statement:

“The Israeli attacks and airstrikes are completely destroying Lebanon’s infrastructure. I condemn these aggressions and call on the Arab League foreign ministers’ meeting in Cairo to take quick action to stop these aggressions. We call on the world to take quick stands to stop the Israeli aggression.”

So suddenly the neoconservatives found themselves in the position of having fought a war to construct a democratic polity in Iraq . . . only for that polity to join Iran and Syria in condemning democratic Israel! The circle closed, and the irony was airtight.

To be fair, some neoconservatives long expected this potential irony. Their ultimate analysis of the Middle East was, to my mind, a largely persuasive one. It was that decades of propping up Arab dictatorships and kleptocracies in return for cheap oil was no longer a viable foreign policy.

The repression in the region had given life and legitimacy to radical Islamism, spawned terror, and eventually cost the lives of thousands of Americans.

The only way to tackle this problem at its roots was to shift American policy towards favouring democracy in the Muslim and Arab world — even if this meant instability and an Islamist explosion in the short term. In the medium and long run, neocons hoped, democratically elected governments would behave more rationally towards the West and Israel — and to their own citizens.

In theory, this makes a good deal of sense — and neocons are, of all people, adept at theory. The trouble, of course, is that theory always melts when it meets something called reality. And non-neoconservatism has always been defined as a political temperament acutely aware of the discrepancy between theory and practice.

It is, from Edmund Burke through to Michael Oakeshott, a tradition that grasps that imperfection, doubt and complexity are the only reliable guides to navigating politics — and life as a whole. Conservatives are not averse to theory or argument — they just understood that it is never, ever enough in the world of practical life.

And so the past few years have witnessed a dramatic encounter between neoconservatism and conservatism, between certainty and doubt, between ideology and pragmatism. Iraq remains the great crucible of this encounter — because it shows that well-intentioned actions can have unintended consequences, that how you do something is often as important as whether you do it, and that distant theory can never be a real match for messy, unpredictable, volatile practice.

And so what you have begun to see in America is a deep and deepening split on the right. The neocons, still steeped in ideological conformity, have responded to setbacks in Iraq and elsewhere with louder calls for upping the ante. The solution to the mess in Iraq is . . . to bomb or invade Iran. The obvious next step in the battle between Hezbollah and Israel is . . . for Israel to re-invade and occupy southern Lebanon. If that fails . . . invade or bomb Syria.

Last week, two deans of neoconservatism issued clarion calls along these lines. The Washington Post’s Charles Krauthammer urged an Israeli ground invasion of Lebanon. The Weekly Standard’s Bill Kristol argued that the best response to the Iranian-sponsored Hezbollah attack on Israel was the following: “We might consider countering this act of Iranian aggression with a military strike against Iranian nuclear facilities. Why wait?” You might say that the mindset of the neocons is very September 12. It has not altered one jot since that day. It is as if we have learnt nothing from the debacle in Iraq about the limits of military force in changing culture and politics in countries we do not fully understand and do not have the expertise or manpower to micro-manage.

It is as if the past five years had never happened — and in the rigid, theoretical worldview of the neocons, they haven’t. But non-neoconservatives have actually observed the past few years and committed the cardinal sin of thinking about them.

Chief among them is George Will, who last week finally unleashed a real tirade against his Republican brethren. He called neoconservatism “a spectacularly misnamed radicalism” and urged patience, prudence and restraint in the war we are now engaged in.

To Kristol’s somewhat hysterical question — why wait to bomb Iran? — Will retorted: “Perhaps because the US military has enough on its plate, in the deteriorating wars in Afghanistan and Iraq, which both border Iran. And perhaps because containment, although of uncertain success, did work against Stalin and his successors, and might be preferable to a war against a nation much larger and more formidable than Iraq.”

Conservatives who believe in limited government and balanced budgets have long since abandoned the Bush administration over its massive spending and contempt for any checks on presidential prerogatives. Conservatives who cherish individual liberty have lost faith in an administration that has wire-tapped Americans without warrants, tortured military prisoners and violated the ancient Anglo-American principle of due process and the rule of law.

Conservatives who believe in political moderation and secularism have long abandoned a Republican party controlled by religious fanatics, who see the separation of church and state as a blot rather than an asset in America’s constitution.

Now, more conservatives are rebelling against neocon over-reach and fanaticism in foreign policy as well. They want to fight Islamist terror — but prudently, carefully and with attention to past failures and new nuances.

A new front has indeed opened up in this war: and it’s a battle for the soul of Anglo-American conservatism. I have a feeling that, as the race for the Republican nomination remains wide open, that debate has only just begun.

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