As wars go, the invasion of Iraq turned out to be surprisingly easy. Saddam Hussein’s fearsome Republican Guards, instead of fighting back, mostly threw away their arms, whipped off their uniforms and fled. It was over in three weeks. The Cassandras who predicted that the invading force was too meager and was spread out too thin were proved wrong again and again.

But the occupation – might as well call it what it is – has already lasted as good bit more than three weeks and promises to drag on for many months or even years. The looting and vandalism were bad enough, but now so-called remnants of Saddam’s loyal forces are staging one attack after another. Die-hard members of his fascist-style Baathist party are joining in a surge of hit-and-run guerrilla warfare reminiscent of the Vietcong resistance in Vietnam and suicide bombings like the Palestinian violence against Israel.

The resistance so far has been increasing rather than decreasing, and the grim struggle to pacify Iraq and help form a peaceable, viable, democratic government to set an example in the far-from-democratic Middle East poses a challenging test for all concerned.

It tests the Iraqi people, who have lived under a harsh dictatorship for 30 years but now face such hardships that some yearn for a return of Saddam, who may actually be hiding in suburban Baghdad, as some informants say,

It tests the American armed forces, who were trained to fight, who fought well, but who now find themselves assigned as policemen and nation builders.

It tests the stamina of the American people. Polls showed that 70 percent of them consistently favored the war. But sticking it out will be tougher and tougher as young American service people continue to die at the rate of one a day and as troops expecting to come home soon find their deployment extended for open-ended occupation duty.

It tests members of the Senate and House who overwhelmingly supported the war and now bear the responsibility for seeing it through to an acceptable conclusion and paying the unexpectedly high costs of the occupation and reconstruction. A further responsibility is to investigate and rectify intelligence lapses that have been exposed.

Finally, it tests President George W. Bush, who remained popular as he waged war in both Afghanistan and Iraq and now must deal with the harsh realities of building a peace that will make it all worthwhile.