So far this month, more than 450 Iraqis and dozens of US troops have been killed by an Iraqi insurgency that, even after two years, shows signs of intensifying. Yet the Bush Administration, which originally expected US troops to be greeted as liberators and then promised that elections would fatally undermine the rebel cause, remains clueless as to the composition of this virulent enemy.

"The Mystery of the Insurgency" was the headline on a Sunday New York Times article reporting on the consensus of U.S. guerrilla warfare experts that the insurgents' motives and actions are simply baffling. However, "it clearly makes sense to the people who are doing it," said defense analyst Loren B. Thompson. "And that more than anything else tells us how little we understand the region."

What we do know about the region is that elements from two formerly implacably opposed forces--secular pan-Arab nationalism and Islamic fundamentalism--have come to be unified, at least temporarily, in their hatred of the US occupation of the historical center of the Arab world. That foreboding alliance is a direct consequence of a White House policy based on willful ignorance of history.

To avenge the 9/11 attack by some of the region's Muslim fanatics, led by Osama bin Laden, President Bush lashed out at the secular regime of Saddam Hussein despite two crucial facts: There was no evidence linking Hussein with bin Laden, and the two were sworn enemies.

As the head of British foreign intelligence reported to Prime Minister Tony Blair seven months before the 2003 invasion of Iraq, Bush was obsessed with overthrowing Hussein, and so "intelligence and facts were being fixed around the policy." That's when the great WMD hoax was launched. But "the case was thin," summarized the notes taken by a British national security aide at the meeting and released earlier this month. "Saddam was not threatening his neighbors and his WMD capability was less than that of Libya, North Korea or Iran."

Nevertheless, thousands of lives and billions of dollars have been spent deposing a defanged dictatorship that posed no immediate threat to the United States, creating a terrorist jungle in its place. We can describe the situation in Iraq today as "mission accomplished" only if our goal was to unite fanatical Islamic jihadis with their longtime enemies, the secular nationalist Baathists.

A major irony in this tragedy is that, according to a Washington Post review of Internet postings paying tribute to the suicide-bombing "martyrs" in Iraq, most of the foreign terrorists wreaking mayhem there come from Saudi Arabia, a nation the United States protected from Hussein's army in the Persian Gulf War. Saudi Arabia also was the country of origin of bin Laden and fifteen of the nineteen September 11 bombers.

To begin to understand the insurgency, the Bush neocons would have to concede that their adventure in nation-building has turned US-occupied Iraq into a deeply alluring target for anti-American rage among Islamic fundamentalists. This Pandora's box once opened cannot be shut by shoving a few ex-Baathists into the new Baghdad government, as urged by Secretary of State Condoleezza Rice on her photo-op visit last weekend.

By all accounts, the disparate elements of the Iraqi insurgency do agree on one thing: their desire to drive the US military out. Thus, the US presence is the fuel for the conflagration it claims to be stamping out.

Yet instead of accepting that the occupation is the chief recruiting tool for both would-be martyrs and less-suicidal nationalist fighters, there is widespread bipartisan agreement in our government that the heavy-handed US presence is the key to restoring order. Leaders of both parties have bought into the fantasy that the January elections proved that a stable, democratic Iraq that will be friendly to the United States is just around the corner.

As usual, they are wrong. Foreign jihadis will keep coming across Iraq's porous borders in search of a bloody martyrs' heaven, Sunni Iraqis will keep fighting for the wealth and power they believe is their birthright, and Shiite radicals such as cleric Muqtada Sadr, popular with Iraq's teeming poor, will continue to denounce the US presence, as he did Monday in Najaf.

The answer is to leave the Iraqis to control their own affairs, rather than pretending to govern from half-empty legislative meetings in the locked-down Green Zone in Baghdad. The United States is now part of the problem, rather than the solution.

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