From Protecting Obama, to Protecting Fellow Marines

As part of our continuing coverage of "Afghanistan: the Road Ahead," - CBS News correspondent Terry McCarthy follows the Third Battalion, First Marines at home, and abroad in Afghanistan.

Corporal Dan Rhodes (left) was sitting on the roof of the patrol base, looking out at a treeline from where the patrol base for Weapons Company had taken fire yesterday.

It was 2 o'clock in the afternoon, about 110 degrees, and he was tempted to take off his Kevlar helmet. But around noon the day before the Taliban had fired a rocket propelled grenade and a long series of automatic weapons' bursts at the roof of the patrol base, and so he wasn't taking any chances.

Rhodes is from Michigan - his dad is a pastor, his grandfather was in the Air Force. He likes to hunt, and he joined the Marines because he wanted to be a sniper. The Marines, he says, have one of the best sniper schools in the military. But at boot camp he got selected to be part of the Marine detachment that provides security for the President. He spent 3 years based in Washington DC - shook hands with both President Bush and President Obama, and even played basketball with the latter.

"I couldn't believe it - I was at Camp David and this Marine asked me if I wanted to play basketball with the President. I said you are kidding, and he said, no, I even have clothes for you to wear". So Rhodes pulled on the T-shirt and shorts, and before he knew it he was standing on a basketball court with the President of the United States. "He asked who the new guy was, and then he shook my hand." Game on.

"President Obama doesn't just talk the talk on basketball - he's really good - it was the President and his Secret Service guys against a team of Marines - they won easily - they crushed us. We stopped keeping count of the score."

Now Rhodes is half a world away from the security bubble that protects the President. Instead he is doing 4 hour posts in the heat of the Afghan sun providing security for the Marines' patrol base, scanning the same treeline over and over with binoculars, looking for any suspicious movement that might indicate another attack is coming. Now and again he blows off the dust that settles on the grenade launcher that is mounted in front of him. It can fire high explosive grenades 2,000 meters - the exploding grenades scare the Taliban, and generally make them fall back. Three high explosive grenades yesterday pretty much stopped the Taliban's shooting from the treeline.

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Rhodes was in Washington until December - having got used to the very cold weather there this winter, his body took a long time adapting to the heat in Afghanistan - worse than his fellow Marines, most of whom are California-based in Camp Pendleton. "On my first patrols my body couldn't even sweat - I had to keep stopping to rest. It's better now, but it was tough at the beginning". He likes his new mission - Weapons Company has heavier weapons than the other three line companies in the battalion, and they are posted right on the frontline between territory controlled by the Marines and territory still controlled by the Taliban. He doesn't mind losing a game of basketball or two - but when it comes to fighting wars, he is looking for a different result.