Not everybody would regard it as a badge of honour to be cited favourably by President Bush in a speech about Iraq, but it happened to me last week when Bush warned that the consequences of leaving Iraq precipitously could be a bloodbath even worse than happened in Indochina after the American defeat in 1975. Alas, I think he is right.

Iraq has certainly not gone the way that I and other supporters of the overthrow of Saddam Hussein had hoped. Some British commentators argue for abandoning Iraq: the consequences, I believe, would be infinitely more horrible than the horrors we see today.

The suggestion ignores the fact that for Islamic extremists, and especially Al-Qaeda, the war to subjugate the West is indivisible. Osama Bin Laden has said that Iraq is the front line. An Al-Qaeda victory in Iraq will strengthen the movement everywhere.

In Bush’s long and rather literary speech – he also referred to Graham Greene’s famous novel, The Quiet American, which scorned America’s efforts in Vietnam – he said: “Recently, two men who were on the opposite sides of the debate over the Vietnam war came together to write an article. One was a member of President Nixon’s foreign policy team, and the other was a fierce critic of the Nixon administration’s policies. Together they wrote that the consequences of an American defeat in Iraq would be disastrous.

“Here’s what they said, ‘Defeat would produce an explosion of eupho-ria among all the forces of Islamist extremism, throwing the entire Middle East into even greater upheaval. The likely human and strategic costs are appalling to contemplate.’ I believe these men are right.”

The two men he was referring to were Peter Rodman, a former aide to Henry Kissinger and more recently assistant secretary of defence in the Bush administration, and me.

When I covered the wars in Indochina for The Sunday Times, I was opposed to the US effort. After the communists won, appalling stories of brutality began to emerge. Thousands and eventually millions of people fled the cruelty of the Vietnamese communist victors, mostly as “boat people”. In Cambodia the Khmer Rouge communist victors were far more brutal and up to 2m Cambodians were murdered or died.

After talking to Cambodian refugees on the Thai-Cambodian border, conducting scores of interviews in America and obtaining thousands of pages of official documents under the blessed US Freedom of Information Act, I wrote a book called Sideshow: Kissinger, Nixon and the Destruction of Cambodia, which was extremely critical of the Nixon White House’s policies towards Cambodia. It argued that American carelessness from 1970-75 helped destroy the country and enabled the monstrous Khmer Rouge to come to power.

Kissinger had declined my requests for an interview before publication but afterwards his aide, Peter Rodman, published, in The American Spectator, a long, detailed and excoriating attack on me and my research. I replied, Rodman counter-attacked and so on – it was interesting and I included the whole exchange in subsequent editions of the book.

Almost 25 years later, after the overthrow of Saddam, which I supported, I finally met Rodman for the first time and I am glad to say we have become friends. Earlier this year we wrote the article that caught Bush’s attention.

Today, as in the 1970s, the press has a special responsibility. In Indochina the majority of American and European journalists (including myself) believed the war could not or should not be won. At the end one New York Times headline read: “Indochina without Americans: for most, a better life”.

Such naivety was horribly wrong, and I have always thought that those of us who opposed the American war in Indochina should be extremely humble in the face of the appalling aftermath. Similarly today I think that too many pundits’ hatred (and it really is that) of Bush (and till recently Blair) dominates perceptions.

Many armchair editorialists seem to dwell more on the American abuses at Abu Ghraib (quickly stopped and punished) than on the horrific, deliberate mass murders committed by the terrorists, both Sunni and Shi’ite. Far too many Muslims have died in Iraq, and the vast majority have not been killed by American or British soldiers. They have been killed by other Muslims.

Above all, we do not pay adequate attention to the millions of Iraqis who (like Vietnamese, Cambodians and Lao 35 years ago) put their faith in the West. The fear of Iraqi interpreters to the British Army being abandoned in Basra is only the tip of the iceberg.

Yet many British commentators and politicians are now suggesting we should abandon Iraq and fight only in Afghanistan. Ironically, this debate is happening when, for the first time, America is making real progress against Al-Qaeda in its strongholds in the northwest of the country and Baghdad. Under one of America’s best generals, David Petraeus, Bush has committed some 30,000 more American troops into these areas and driven Al-Qaeda out.

Local insurgents have been revolted by Al-Qaeda atrocities – decapitating babies, slicing off people’s faces with piano wire, using chlorine gas tankers and vast car bombs as weapons of mass destruction to kill as many innocents as possible – and have rallied to the government. Confidence is beginning to return: even Fal-luja, a hell of torture chambers and Islamist violence until US marines drove Al-Qaeda out, now has a growing chamber of commerce.

Next month Petraeus has to testify on successes and failures in Iraq to Congress, where both Republicans and Democrats are increasingly sceptical if not downright hostile to the president’s policies. He can justifiably praise the courage, commitment and successes of his soldiers. But alas their progress has not been matched by reconciliation and progress between the Sunni, Shi’ite and Kurdish members of the Iraqi government. That is where the real threat to Iraq now lies.

The consequences of an American defeat in Iraq are likely to be even worse than in Indochina. As Abu Musab al-Zarqawi, the Al-Qaeda leader in Iraq, said before he was fortunately killed by a US airstrike: “The shedding of Muslim blood is allowed in order to disrupt the greater evil of disrupting jihad.” Islamist revenge on all those Muslims who have tried to build a better Iraq will be terrible.

Why do the horrors inflicted by Islamic extremists in Darfur seem to appal us, more than those in Iraq? Because, I suppose, in an orgy of self-deluding hypocrisy, we prefer to blame the United States. We should grow up.

The horror of Darfur will pale beside the bloodbath in Iraq if we withdraw before we have done everything possible to enable Iraqi security forces to defend their country against sectarian horrors. I hope Gordon Brown and his advisers realise the impression that we are seeking to leave will guarantee defeat. In global jihad, perception is a more important weapon of war than ever before.

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