The numbers of U.S. servicemen killed, wounded or missing on the Iraqi battlefield are mounting steadily, and military experts warn that Americans might soon be confronting military carnage they have not seen since the Vietnam War.

About 30 U.S. servicemen have been publicly reported killed in a week of combat, along with 20 British soldiers and marines. But that total could be considerably higher, because news from the battlefront has been slow to be tallied. The number of wounded appears to be soaring.

Officials at Camp Lejeune, N.C., released a curt tally yesterday morning, listing 11 Marines from the 2nd Expeditionary Force as missing within the past 24 hours and 14 as wounded in action in fighting near Nasiriyah. Defense Department officials quickly informed the public affairs office at Camp Lejeune that the release was a violation of Pentagon policy, said Marine Maj. Michele Flynn, a base spokeswoman. Casualty totals are supposed to come from Washington, and the Pentagon has released those numbers reluctantly.

Reports from the battlefield tell of violence that is not reflected in the upbeat assessments issued at press briefings at the Pentagon and Central Command in Doha, Qatar. More than half of a contingent of 120 Marines were wounded Wednesday when they were hit with gunfire and rocket-propelled grenades on the approach to a bridge at Nasiriyah. Fifteen of their Humvees and seven-ton trucks were destroyed.

"Nasiriyah was supposed to be a six-hour fight," a wounded gunnery sergeant said at a field hospital yesterday. "It's already been five days. Five days of nonstop, 24-hour fighting."

Body armor that protects the head and torso has done wonders to keep troops alive, but officials at Walter Reed Army Medical Center in the District have been told to prepare for an influx of wounded soon.

"We don't really know if the country will accept casualties like this because it hasn't been tested in 30 years," said Charles Moskos, a Northwestern University sociologist who has studied the reaction of the public and the military to casualties.

More Americans have already died in Iraq than have been killed in the military's war on terrorism since it was launched after Sept. 11, 2001. The Defense Department lists 20 deaths by hostile action in Afghanistan, the Philippines and the Persian Gulf until the invasion of Iraq.

In the 1999 air war over Kosovo, the United States did not suffer a single battlefield death.

In the Persian Gulf War 12 years ago, there were 147 deaths on the battlefield; 235 were killed in accidents and other noncombat situations. But that conflict stretched over nearly six weeks. At the rate that Operation Iraqi Freedom is going, the United States could expect 180 deaths in that length of time -- but extrapolating from the opening week may be pointless.

Defense Secretary Donald H. Rumsfeld warned yesterday that the hardest fighting is to come, when allied troops confront Saddam Hussein's Republican Guards and Special Republican Guard troops ringing Baghdad and his hometown of Tikrit, then try to capture the capital. On the other hand, the Iraqi government could collapse with the first Republican Guard clash.

Even the Gulf War's tally is relatively bloodless, when compared to the 58,203 who died in Vietnam, the 36,568 who died in Korea, the 405,399 who died in World War II and the 116,516 who died in World War I.

Whether the current casualty rate is politically sustainable is highly uncertain. A poll conducted in February by Steven Kull, director of the University of Maryland's Program on International Policy Attitudes, found that Americans believe 1,000 servicemen and women would lose their lives in a war with Iraq, a number that they by and large could accept.

But those expectations of significant casualties plunged as the war approached. By March 20, a Washington Post poll found that only 37 percent expected the United States to suffer significant casualties.

"That suggests recent experiences with war did influence expectations in the public about what will happen," said James Burk, a sociologist at Texas A&M University who has studied public response to casualties.

Some experts say politicians tend to underestimate the public's capacity to accept death and injury on the battlefield. Burk said that as long as the public believes the war is being conducted reasonably, casualties will only bolster the public's resolve, especially if the Iraqis are inflicting them with guerrilla tactics that Americans believe are beyond the pale of decency.

When more than 200 Marines died in a 1983 suicide bombing in Beirut, the public wanted to stay the course, Burk said. It was only when the political leadership in Washington and abroad began to fracture that the Reagan administration had to pull U.S. peacekeeping forces out.

In contrast, public opinion had already turned against U.S. military operations in Somalia by the time Special Operations forces lost 19in a single battle in Mogadishu, Burk said. By October 1993, a military deployment that started as a humanitarian relief operation had evolved into a bloody, seemingly fruitless police action.

"Somalia is a case where we see how understanding the reasonableness of the mission is more important for public support than the taking of casualties," Burk said.

Kull largely agreed. Three factors appear to influence the American public's willingness to accept casualties: whether the conflict is legitimate in the world's eyes, whether its goals are worthwhile, and most important, whether the campaign is succeeding.

That presents a mixed outlook for the current war, he said. So far, the public sees the campaign as succeeding, and that has overcome the negative influence of worldwide opposition. For the most part, the public sees the goal of stripping Iraq of weapons of mass destruction and overthrowing Hussein as worthwhile.

But danger lies in the failure so far to find caches of chemical, biological and nuclear weapons, Kull warned. Couple that with continuing international protests, and it is not hard to see why Pentagon officials have repeated incessantly that the military campaign is on track and proceeding successfully.

Moskos raised another concern, a factor that he believes is a truism in warfare: "The country will accept long-term and heavy casualties only if the children of the privileged are willing to put their lives on the line."

In an all-volunteer military there is no sign that will happen, he said, concluding: "I don't think we're going to be willing to take casualties."

Correspondent Peter Baker contributed to this report from Camp Viper in southern Iraq.

Medical personnel carry an unidentified injured Marine to a waiting ambulance after the soldier was flown out of central Iraq on Thursday. The Marine is expected to recover, but as the number of war casualties mount, public support for the war might drop. Shelley Pokorney, with family members at her side, talks about her husband, 2nd Lt. Frederick E. Pokorney, killed in Iraq.Army Sgt. Charles Horgan is recovering at the U.S. Medical Center in Landstuhl, Germany, from injuries suffered in Iraq.