Laurence Freedman: History shows that US leaders do 'cut-and-run'

Beirut and Vietnam demonstrated that the US public would accept sacrifices but not for a failed policy

The goal of stability in Iraq has now been set up as a race between two political processes: George Bush's drive to avoid his father's fate as a one-term President and the attempt to establish a credible and broadly legitimate government in Iraq in time to drain support from those currently promoting instability.

The motley collection of Ba'athists, Islamic militants (local and imported) and criminals responsible for the murder and mayhem are well aware of this political context. They are not alone in asking if Bush can be re-elected on the basis of an Iraqi policy that is now endorsed by barely half the population, down from as much as 80 per cent during an apparent moment of triumph in April.

The enemies of the American occupation in Iraq lack ideological coherence. Some are secular, some religious; some embrace martyrdom and others shy away; some target only Americans while others will go for anyone trying to bring hope to Iraq. If they have any goal in common it is to render Iraq so unsafe and ungovernable that the Americans will give up on the whole enterprise and go home.

This strategy assumes that when the going gets tough the Americans become quickly frustrated and discouraged. The White House's sudden shift to more local solutions to the Iraqi problem, welcome as it may be to the rest of the international community, may even be taken as an indication that the strategy is working.

The most famous precedent for the interaction of military strategy and the US electoral cycle is the Tet offensive launched by the Viet Cong in February 1968. After optimistic US military claims about the war's progress, the enemy appeared suddenly in strength in the key cities of South Vietnam. Though the offensive was a military catastrophe for the Viet Cong, politically it was a victory.

Up to this point half the American people had believed that progress was being made in the war (though casualties were about 20 times Iraq levels); after the Tet offensive this slumped to a third, with a quarter believing that the US was losing and the rest seeing only a miserable stalemate. In March, President Johnson announced that the bombing of North Vietnam would be suspended, that negotiations would be sought and that he would not seek re-election.

In the Middle East the most telling episode came almost exactly 20 years ago. Early on 23 October 1983, a suicide bomber crashed an explosive-laden truck killing 241 marines and other US personnel (not far off total combat losses in Iraq this year) as they slept in their compound at Beirut airport.

This is normally recalled as prompting the immediate abandonment of the US peacekeeping role in Beirut. Actually the story is more complex. The initial assumption was that the attack made withdrawal impossible. The marines were replaced and in early December retaliatory air strikes were launched against Syrian and Islamic militant positions.

But the Lebanese Army had just collapsed, the government was unravelling. The next day an American professor at the American University of Beirut was kidnapped by Muslim radicals - the first of many (and a tactic yet to be employed in Iraq). On 7 February, Reagan reversed himself and announced that all US Marines would shortly be "redeployed".

The conclusion drawn by America's enemies, to be reinforced in Somalia a decade later, was that fear of casualties represents the superpower's greatest vulnerability.

President Bush, most recently in London, has challenged this view robustly. It is worth recalling that the Americans did not actually leave Vietnam for another five years after the Tet. The scale of the US military, economic and political investment in Iraq is immense. American politicians, however regretful of the war, are aware of the consequences of walking away.

The Democratic Presidential hopefuls have good points to make about how Bush got the country into a mess but did not necessarily have any better ideas about how to get out. Senator John McCain, referring back to Vietnam, has noted that the imperatives of the electoral calendar still apply: "watch February and March if we don't see things improve". Even on the most optimistic interpretations the revived Iraqi political process will still be at a tentative stage, and possibly extremely difficult as the different factions and groupings jockey for position and present their constitutional demands. These are circumstances which encourage demagogues, corruption and private armies. Beirut and Vietnam demonstrated that the American people would accept sacrifices but not in support of a failed policy, and also that a successful policy depends on getting the local politics right. There is some evidence that these messages have got through, although some of the implications (such as being nice to Iran) are unpalatable.

While many positive things are starting to happen in Iraq, and the main trouble is confined to the "Sunni triangle", there is no reason to suppose that over the short term the good days are going to outnumber the bad. For the next few months they will seek to panic Washington, clinging to the hope that Bush might not be the first American President to promise that his country would not "cut-and-run" and then do precisely that.

The author is Professor of War Studies at King's College, London