Just days after passing one difficult anniversary, that of the fifth year of the Iraq war, another grim milestone was reached on Sunday night. According to an Associated Press tally, the death of four U.S. soldiers during a roadside bombing attack brought the American death toll to 4,000. And that number will inevitably rise as President Bush and, more than likely, his successor continue to grapple with how to end American involvement in the country.

Even as a slow troop drawdown continues, following last year's surge, 160,000 U.S. forces are in Iraq and 130,000 are likely to remain there by summer, leading veterans and pundits to wonder how much higher the toll could go.

"When taken into context — and you think about other major wars, like the world wars, where hundreds of thousands died, or Vietnam, where it was close to 60,000 — in that context, 4,000 is a much lower number," said Jason Campbell, research analyst at the Brookings Institution. "But, for World War II, as high as the fatalities were, there was never a time when it was seen as an unworthy cause. As Vietnam dragged on, and it became more of a flashpoint for society, and you saw larger demonstrations, then that number became more significant."

Speaking last week on the anniversary of the war, Ohio Iraq veteran Chris Herzfeld said he knew from his first and only tour of duty, during the initial invasion of Baghdad in 2003, that the U.S. would still be in the country, suffering casualties five years later.

"Historically, if you look at our conflicts from the past, I knew we'd be there for a minimum of 10 years, if anything is to truly be resolved," said Herzfeld, who is finishing up his junior year as a business major at Miami University in Oxford, Ohio. "The way this country looks at it is such a pop-culture-generation [view]: 'I'm tired of the war, what's on TV? I'd rather watch "Idol." ' I'm thinking we probably should not have gone in the first place, but now that we're there, we will probably have to stay."

That was the same message the president's press secretary gave on Monday (March 24) when reporters asked Bush how he felt about the 4,000th combat death. According to CNN, White House spokesperson Dana Perino said the president was aggrieved by the deaths, and he realizes that he bears a responsibility for every death in the conflict, but that every time he meets with the families of soldiers, they tell him they want him to complete the mission. Despite the overall downturn in violence, 2007 was the deadliest year so far in Iraq, with 901 U.S. deaths.

The total death toll in Iraq is considerably lower than other conflicts in U.S. history that lasted as long or ended earlier, due in large part to advances in armoring and battlefield medical science, which have saved more lives but also resulted in tens of thousands of veterans with seriously debilitating but not life-threatening injuries.

Anthony Cordesman of the Center for Strategic and International Studies, who has long been critical of the administration's policy, said nobody can point to a finish line in the conflict because there are too many variables and uncertainties.

"Everybody would like to simplify and predict, but you can't," said Cordesman. "We've had scores of significant military gains lately, but you can't defeat al Qaeda completely. If you can move toward reconciliation, improve Iraqi governance, create more jobs and better Iraqi forces, then Iraq should be able to stand up on its own by the end of the next administration. But that's a lot of ifs."

And, even if the next president, whether a Democrat or Republican, does decide to pull out U.S. troops quickly, that doesn't mean the death toll won't continue to climb in the interim. "If you took all U.S. forces out of Iraq, it would take a year to do it, or you would have to abandon or destroy a massive amount of equipment and create a power vacuum that would leave the region open to Iranian influence," he said. "Any president, Republican or Democrat, will have to look not only beyond Iraq but to what happens in the Gulf as a whole."

While the surge seems to have worked — the average death toll in January 2007 was around 100 per month and by the end of 2007 and beginning of 2008 it was closer to 35 per month — Campbell said death counts are not the best indicator of how the U.S. is doing in Iraq.

"When the death-toll numbers became more publicized in recent weeks, a very low percentage of people knew where we were in that count," he said. "There's a psychological significance for some in the general public, but by and large, the average American has not been affected by what is happening, because unlike the world wars or Vietnam, the average American has not been asked to sacrifice. Sometimes it takes these landmark figures to kind of let people reassess what's going on and get things to the front burner again."

Find out what the Democratic presidential contenders had to say about the Iraq war during "Choose or Lose Presents Clinton & Obama Answer Young Veterans."

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