President Bush and his aides sound distinctly less triumphal these days about the prospects for early success in the continuing war in Iraq -- a deliberate change in tone after a week of setbacks on several fronts.
A series of newly sophisticated attacks by anti-American insurgents -- including a missile strike on a U.S. helicopter Sunday that killed 16 soldiers and injured 20, the deadliest single attack since U.S. forces invaded Iraq in March -- has made the administration's claims of progress look shaky, at least in the short run.
And as political sniping over the war stepped up in Washington, it became clear that the president faces not one but two implacable enemies: the rebels in Iraq plus the relentless pressure of time in an election year.
Military experts say it takes time, and troops on the ground, to defeat a well-entrenched insurgency -- more time and troops than the Bush administration initially wanted to spend. But the longer the struggle takes, experts warn, the greater the danger that support for the war effort, among Iraqis and Americans, will waver.
"The longer this lasts -- the longer the enemy can create chaos -- the more likely the advantage will shift to his side," warned retired Maj. Gen. Robert H. Scales, a former commandant of the Army War College. "I happen to believe that's not going to happen. The indicators of stability are progressing, and the number of Baathists is finite.... But it could."
So as Bush and other top officials last week launched a new round of their public campaign to bolster support for the war, there was less bravado than before and franker warnings of further setbacks ahead -- even before Sunday's deadly attacks, which killed a total of 19 Americans, including the 16 aboard the helicopter.
"Iraq's a dangerous place," Bush said in a news conference Tuesday. "I can't put it more bluntly than that. I know it's a dangerous place. And I also know our strategy to rout them out ... is the right strategy."
Defense Secretary Donald H. Rumsfeld was more blunt.
"In the last three or four weeks, we've seen an increase in the number of incidents per week," he said. "I think that reasonably we have to expect that that will go on for a bit.... I'm not putting a positive spin on it," he added. "This is a rough business.... It's a war, a low-intensity conflict that's taking place."
That was a shift, in tone at least, from earlier pronouncements, when Bush said the escalating attacks were a reaction to U.S. progress.
Those comments drew public criticism from Democrats, including several presidential candidates, as well as some Republicans.
"When there's a rocket attack on the Rashid Hotel when the deputy Defense [secretary] is there, it is not a sign that we're winning," said Sen. John McCain (R-Ariz.), one of the GOP's most frequent critics of the administration. " 'Duhhh,' as my kids say."
Bush, asked Tuesday whether voters might be impatient with a long war, responded mildly: "I think the American people are patient during an election year, because they tend to be able to differentiate between, you know, politics and reality."
But an aide, speaking on condition of anonymity, said irritation at the White House about the sharpening domestic debate was rising. "There are a lot of people who have honest criticisms of our policy, but there are more who want to make facile comparisons to Vietnam for political purposes," he said.
Public support for the U.S. occupation of Iraq has remained strong in recent weeks, but polls have found increasing doubt about Bush's handling of the situation -- doubt that has become a central theme of the Democratic presidential candidates' campaigns.
Deputy Defense Secretary Paul D. Wolfowitz complained last week that the debate over Iraq in the presidential campaign was harming U.S. efforts to recruit Iraqi allies.
"It sends a very unsettling message to Iraqis that our elections might decide their future," he told students at Georgetown University. "When they hear the message that we might not be there next year, they get very scared, and that fear leads them not to give us information about where the bad people are; it leads them not to want to serve on the town council; it leads them not to want to risk their lives as policemen."
No major Democratic candidate has proposed withdrawing U.S. troops from Iraq.
Nevertheless, Scales and other military experts said, it is true that Iraqis are trying to gauge the depth of the U.S. commitment to decide whether siding with the Americans is worth the risk.
"We're looking, in essence, at a test of will," said Scales, coauthor of "The Iraq War," a book on the U.S. invasion. "They have little military power but enormous will. Our situation is just the opposite: We have enormous military power, but our will is uncertain.
"In the Middle East, indigenous armies fighting against Western-style armies are 0-7, you could argue, since 1948 -- but in unconventional warfare, they're 5-0," he said, citing the 1983 bombing of U.S. Marines in Beirut as an example.
Administration officials, many of their critics and outside experts agree that more forces are needed to defeat the insurgency; the question is where they come from and how soon.
"Everyone agrees that we need more troops on the ground in Iraq; they just can't agree on more of what," said James Dobbins of the Rand Corp., an expert on postwar reconstruction. "Conservatives want more U.S. troops. Liberals want more allied troops. The Pentagon wants more Iraqi troops. My view is that they're probably all right: We're going to need all three."
So far, the Bush administration has said there is no need to increase the number of U.S. troops in Iraq above the current level of about 130,000. Instead, the Pentagon plans to replace some of the heavy infantry units in the country with lighter units more attuned to small-scale counterinsurgency warfare. Much of that rotation is scheduled to occur next spring, as units now in Iraq complete a one-year deployment.
Rumsfeld said Sunday that he suspected he would be able to reduce the number of U.S. troops soon. "It's come down from 150,000 to 130,000, and I suspect it will continue going down ... if the security situation in the country permits it," he said on NBC's "Meet the Press."
Meanwhile, Rumsfeld and aides say, they are working to accelerate the training of Iraqi security forces -- principally policemen and civil defense units -- to take on more of the anti-insurgent campaign.
"It will not be long before they will be the largest [contingent] and outnumber the U.S. forces," Rumsfeld told reporters last week, displaying a chart that showed the total number of Iraqi security forces, including guards at public buildings in Baghdad, already at about 100,000.
But that progress is not fast enough for some.
"The time window is three to six months in which we have to succeed, in my view," McCain said. "We've got to address the problem by more troops of the right kind -- counterintelligence and counterinsurgency.... We still need more Marines. We still need more Special Forces. We need people who speak the language. And we need it quickly."
Moreover, U.S. officials appear to have largely abandoned their hopes for significant additional help from allied countries. Turkey had agreed to send 10,000 troops to southern Iraq, but objections from Iraqi leaders have put that plan on hold.
"We're going to need to increase the number of indigenous forces or get somebody else to do it," Scales said. "You just have to look at the math.... There are probably only about 60,000 people out of 1.2 million [U.S. troops] that do this kind of work -- patrolling, low-intensity engagement. Most people don't understand how tiny the American military really is ... when it comes to close combat.
"Over time, somebody else is going to have to take up the heavy lifting," he warned, "or this force is going to break."