Program Note: Tune in Tune in tonight for live coverage of President Obama’s speech on Afghanistan. Earlier this fall, Anderson, Peter Bergen, Dr. Sanjay Gupta and Michael Ware reported on the U.S. war in Afghanistan and the challenges U.S. troops were facing in Helmand Province. AC360° tonight at 10 p.m. ET.

U.S. Marines listen to a brief before heading out on patrol in Helmand Province.

Anderson Cooper | BIO
AC360° Anchor

"What’s your blood type?"

It’s the question you’re asked around here a lot. Before getting into a helicopter, before going out on patrol with a new unit. "What's your blood type?"

The Marines have their blood type sewn into the patches they wear along with their name and rank. Many write it in black marker on the band of their goggles. I know some guys who even have it tattooed on their chests, just above their heart. Blood types are displayed prominently in case something goes wrong – in case they get hurt. Doctors can treat them faster in an emergency if they know what blood type to use. At first, the question surprised me, now it’s just a routine part of the introduction.

When you’re an embedded reporter moving from base to base, you meet new Marines all the time. At first some are wary of reporters, but go out on a foot patrol with a platoon for several hours in a combat zone, and very quickly the wariness breaks down, especially when they see you don’t have an agenda.

"My wife emailed me," one Marine said to me this morning. "She said you're reporting the real stuff we're doing here. Thanks." He made my day.

I know it sounds corny, but it's impossible not to want to do right by these Marines. To get the story right. They are separated from their families, far from home, living in dust and dirt, putting their lives on the line every day.

They are doing it for their families, for each other, and for us, but they are also doing it for Afghans, many of whom are still on the fence about their presence here.

Most people in the U.S. probably think this war is all about hunting down the Taliban. It's not. The mission is far more complex. The Marines’ goal in Helmand province is to protect the population.

This is not a war about territory, or enemy body count, it is about protecting people, building confidence, convincing Afghans to choose sides. This is not the traditional role played by Marines, but they are adapting, and despite frustrations, and growing losses and difficulties, the Marines I'm with express a real sense of accomplishment and deep pride.

Many Marines here have already done multiple tours in Iraq. For others, this is their first deployment. I’ve met career Marines here, and some young men who plan to get out of the Corps as soon as their enlistment is up. Some love the mission, others can’t wait to get out.

The Marines here are as varied as the American population. What sets them apart, however, what they have in common, is their dedication. Despite their differences as individuals, they are willing to sacrifice for a common goal. It is humbling to witness. It is, I think, important to remember.