Politicians have made it the most important issue of the upcoming election, arguing back and forth over strategies, resources and timetables. Public support falls as death tolls steadily rise. All the while, our reasons for being there adjust and transform, sometimes gradually, sometimes in the time it takes to make a speech or topple a statue.

Much has changed since the beginning of the war in Iraq, which marks its fifth anniversary on Thursday (March 20). One thing that hasn't is the reality the military faces every day, say the cast of "Stop-Loss," a drama about a decorated sergeant who returns from Iraq only to learn that he is being sent back. The actors base their assertions on conversations they've had with current and former soldiers.

(Don't miss "Choose or Lose Presents Clinton & Obama Answer Young Veterans," which premieres Thursday at 6 p.m. ET on MTV, MTV2, mtvU, MTV Tr3s, MTV Hits and MTV Jams — head here for additional material, including profiles of the Iraq veterans featured in the show.)

For instance, while much of the country argues over politics, "soldiers have to check their politics at the door," co-star Channing Tatum said.

"It's their job. That's how I think [they] all sort of went into it," he said. "[They] put all of our political agendas aside and went, 'Nope, we're just going to be soldiers.' "

"When I used to think about the war, I would think about it from an intellectual point, analyzing, 'What's the government doing, what's the economy doing, where's the oil?' " Joseph Gordon-Levitt said. "But getting to know some soldiers who have been over there made me consider [it] on a whole other, more human and personal level, rather than thinking of these guys as simply numbers and statistics."

"It wasn't about how we should end the war," star Ryan Phillippe recalled of his conversations with soldiers. "I think those are bigger questions than ones the average soldier wrestles with. They're more concerned with life and death and getting home to see that girl they love or children they left back here."

As Phillippe suggests, any war story is by necessity a multifaceted narrative. There's the immediate, primal experience of soldiers in war, an experience that can be indescribable and beyond a civilian's comprehension (think of the storming of the beach in "Saving Private Ryan"). There are the stories soldiers tell themselves to make sense of their environments — sometimes not accurate, but always truthful. Then, lastly, there are the political justifications given for fighting: retribution, defense, God, honor, the flag, etc.

Because soldiers are more preoccupied with the "how" than the "why" of battle, say the actors, their immediate perceptions rarely change, regardless of how the war plays out at home, regardless of the anniversaries we choose to observe.

"This is what was so hard for me to understand at first and what I really came to learn," Gordon-Levitt said. "When you're sitting in your living room reading the news and watching TV, these are the kinds of questions that come up: What's gonna happen in 15 years, what's it gonna mean for the diplomacy between the United States and the Middle East? [But] when you're actually over there, you can't afford to think that way. It's different — it's something, I think, that is deep inside your body that happens when your life is threatened."

"I was looking for the emblematic story for this generation, which I found to be fundamentally patriotic Americans who signed up [and] wanted to defend their home, their country and their family," writer/director Kimberly Peirce said. "When they got there, they had a very profound experience. They realized that being in combat was about protecting the soldier to your left and the soldier to your right. That's really it."

So the "Stop-Loss" gang insists that while it's inevitable that, on the occasion of the fifth anniversary, we reflect on how public perception of the war has changed, it's important to shift our perspective from a political viewpoint to one of "human terms," Gordon-Levitt said.

Luckily, we live in just the right time to do that.

"Just accepting mainstream media is unacceptable to an extent because most of the people in mainstream media weren't there," Gordon-Levitt contended. "[But] the Internet generation has an opportunity no other generation has had to be in communication with the soldiers themselves. There are more blogs and Flickr accounts and stuff from soldiers than you could possibly go through. Check it out."

"Stop-Loss" opens March 28. Hear what soldiers have to say at the movie's Web site.

Get into the discussion! Watch "Choose or Lose Presents Clinton & Obama Answer Young Veterans" on Thursday at 6 p.m. ET on MTV, mtvU, MTV2, MTV Tr3s, MTV Hits or MTV Jams.