In his continuing attempts to justify escalation of the war in Iraq, President Bush has resorted to historical analogy, warning that a hasty retreat from the Middle East would trigger a bloodbath as it did in Cambodia and Vietnam in the 1970s. Not only is the comparison faulty, it is historically inaccurate.

"In Cambodia," Bush said, "the Khmer Rouge began a murderous rule in which hundreds of thousands of Cambodians died by starvation and torture and execution" and "in Vietnam, former allies of the United States, and government workers and intellectuals and businessmen were sent off to prison camps, where tens of thousands perished. Hundreds of thousands more fled the country on rickety boats, many of them going to their graves in the South China Sea."

Bush and defenders of the current war and Vietnam ignore crucial aspects of history, however. Vietnam by 1975 had been wracked by a brutal fratricidal war for over a quarter-century, and recriminations were unavoidable, and made inevitable by the nature of the U.S. intervention and occupation of the southern half of Vietnam.

His analogy of Cambodia is more off-track. The Khmer Rouge slaughter was not caused by the U.S. withdrawal from Indochina in 1973, but by the U.S. escalation of the war and intervention into Cambodia in the years prior to that time. The United States had been conducting a "secret war" kept secret from the American people but not from the Cambodians on the receiving end of B-52 strikes since the later 1960s. In April 1970, then, Richard Nixon authorized what he called an "incursion" of Cambodia on the pretext of destroying the headquarters for Vietnamese Communist military operations there, the so-called COSVN, or Central Office for South Vietnam.

A month earlier, however, in March 1970, the United States had facilitated the ouster of the Cambodian head-of-state, Prince Norodom Sihanouk, and replaced him with a weak but pliable politician named Lon Nol. At this time, the Khmer Rouge was a small splinter group of the far left, without much popular support or military power. But the U.S.-sponsored coup, and the subsequent invasion in April, proved to be a great blessing to the Khmer Rouge. With Sihanouk, who had tried to remain neutral in the larger Indochinese conflict and thus was not preventing either the Vietnamese Communists or the U.S. from operating in Cambodia, out of the way and Lon Nol, perceived as a "puppet" of Nixon, in office, there was no middle ground in Cambodia. As a result, the Khmer Rouge soared in influence and popularity by exploiting the heavy-handed American political and military intervention.

By the mid-1970s, as the U.S. air war against Cambodia continued, killing hundreds of thousands of Cambodians, the Khmer Rouge was well-positioned as the anti-American and anti-Lon Nol alternative, and so was able to swarm into Phnom Penh and establish a regime in April 1975, and then unleashing a genocidal wave of killings that lasted until the Vietnamese intervened and ousted the Khmer Rouge leader Pol Pot in January 1979. Even after that ouster, however, the United States continued to work with the Khmer Rouge, supporting covert operations against the Vietnamese-supported new government in Phnom Penh and even, in the Ronald Reagan years, supporting the Khmer Rouge claim to Cambodia's seat at the United Nations.

Now, as in the Vietnam era, the United States finds itself in a similarly intractable position. By intervening in a country that was not stable to begin with, putting a government into power that is derided as a U.S. client regime, heightening internal struggles, this time between Shiite and Sunni, taking sides in a civil war, causing massive destruction, and continuing to fight amid escalating bloodshed abroad and popular protest at home, the Bush administration is making many of the same errors that the Johnson and Nixon administrations did during the Vietnam War. While there does not appear to be a genocidal Khmer Rouge-type group lurking in the background and ready to cause incalculable terror, there is no question that the various armed groups that have emerged in Iraq since March 2003 are certain to persist and cause greater mayhem and death, perhaps throughout the entire Middle East.

So Bush's analogy is not only incorrect, but exposes the perhaps unavoidable fate facing the United States in Iraq. Continuing this war amid the daily deterioration will only prolong the time it will take to rebuild Iraq and try to heal the hatred and fear that now engulfs it. The sooner the United States begins a timely withdrawal from Iraq, the sooner the Iraqis themselves can begin to sort out their problems, and hopefully prevent a repeat of the killing fields of Cambodia.

Buzzanco is professor and chair of the Department of History at the University of Houston. He is also author of "Masters of War: Military Dissent and Politics in the Vietnam Era and Vietnam and the Transformation of American Life." Readers may e-mail him at buzz@uh.edu.