The two men’s testimony on Sept. 10 reportedly buoyed the spirits of some Republicans. G.O.P. die-hards claimed to see in it the potential to improve their party’s lowly standing with the American public.

Conversely, even though General Petraeus’ optimism was limited and tightly qualified, its mere existence was enough to dismay Democrats and liberal activists.

Representative Tom Lantos on Monday accused the general of having been sent by the administration to persuade Congress that “victory is at hand.”

The liberal group MoveOn.org didn’t even bother waiting to hear what the general had to say. “General Petraeus or General Betray Us?” ran the rhetorical question atop its full-page ad in The New York Times.

The partisans on both sides ignore huge parts of the picture. Republicans are surely living in dreamland if they believe that the American public will forgive the Bush administration its colossal missteps in the early years of the war.

Those errors are not erased, nor are their catastrophic consequences lessened, merely because General Petraeus and Mr. Crocker appear to have had a degree of success in their efforts to impose some sense of order in parts of Iraq.

A New York Times/CBS News poll released on Monday asked respondents whether they approved or disapproved of the way President George W. Bush was handling the situation in Iraq. A massive 71 percent disapproved.

But the judgments proffered by General Petraeus and Mr. Crocker also brought the intellectual inconsistency of the “Troops Out Now” segment of American liberalism into sharp focus.

Both men emphasized the havoc that would be the near-inevitable result of hasty withdrawal.

“A premature drawdown of our forces would likely have devastating consequences,” Mr. Petraeus said. He then referred to an intelligence report that enumerated some of the dangers, including a high risk of disintegration of the Iraqi security forces and a marked increase in sectarian violence and displacement.

Mr. Crocker expressed his certainty that “abandoning or drastically curtailing our efforts will bring failure, and the consequences of such a failure must be clearly understood. An Iraq that falls into chaos or civil war will mean massive human suffering—well beyond what has already occurred within Iraq’s borders.”

The gravity of those assessments stood in stark contrast to the shallowness of some of the arguments coming from the Democratic Party, many of whose members seemed to regard the Petraeus testimony as, more than anything else, a political inconvenience.

Even in the course of praising the general personally on the day of the testimony, Representative Ike Skelton, the Democratic chair of the House Armed Services Committee, said that General Petraeus was “the right person, three years too late and 250,000 troops short.”

That was a cute enough sound bite. But while it sought to replay for the millionth time the debate over how the U.S. got into the war in Iraq, it displayed no leadership or depth of thought about how to make the best of the current situation, and what responsibility America now bears to prevent things from getting far worse.

If opinions about what to do in Iraq could be untangled from views of the Bush administration, it might be possible to have an honest debate about the consequences of a rapid American pullout.

Instead, we are treated to glib remarks even from some of the nation’s foremost politicians. “There is no military solution,” Senator Hillary Clinton said on the night before the testimony. “That is why I believe we should start bringing our troops home.”

It was a dispiriting non sequitur from a woman who is known as one of the more realistic voices in the Iraq debate. There is indeed no exclusively military solution. But that doesn’t change the fact that American troops are an essential part of any attempt to get Iraq back on its feet, since they appear to be needed to provide the security that might allow political progress to gain traction.

The thinking of other leading Democrats seems to trundle along even more predictable and flawed lines. The progression seems to be: Bush is bad; Bush doesn’t want withdrawal; therefore withdrawal is good.

In a Washington Post op-ed on Saturday, presidential candidate Bill Richardson exhibited an abundance of wishful thinking.

Mr. Richardson asserted that “only a complete withdrawal can … break the deadlock that has been killing so many people for so long.”

But it is not “deadlock” that has been killing people. It is gangs of heavily armed religious fanatics and assorted other thugs. To suggest that a U.S. withdrawal would lead those groups to come to some kind of amicable understanding is risible.

Those who favor an immediate American withdrawal from Iraq bridle at being described as “irresponsible.” That is fair enough when Republicans throw out the term as a thinly disguised code for “cowardly” or “traitorous.”

But at a much more fundamental level, the U.S. does indeed have responsibilities toward Iraq. They do not just begin and end with Colin Powell’s famous injunction that “you break it, you own it.”

The U.S. sought to create a new, free Iraq. Millions of Iraqis joined with it in that project, at mortal risk to themselves. They were badly let down by America’s blunderings and botches.

But to abandon them too hastily, too selfishly or too thoughtlessly would be the greatest betrayal of all.