The loner to be awarded a Medal of Honor

For more, watch "Jake Tapper Reports: An Unlikely Hero" tonight August 21 at 10 p.m. ET/PT. Jake Tapper, host of "The Lead" and CNN's chief Washington correspondent, is the author of the best-selling book, "The Outpost: An Untold Story of American Valor."

When Pvt.Ty Carter first arrived in Afghanistan, he took one look at his surroundings and thought, "This is a death trap."

He would soon learn just how right he was.

Combat Outpost Keating was a sitting target for nearby Taliban insurgents: It sat deep within a valley, surrounded by mountains.

The American soldiers stationed there knew it was only a matter of time before something bad happened. "We just didn't know when," Carter said.

When it did, the assault would set in motion a chaotic chain of events that had every soldier certain he would not make it out alive.

Eight American soldiers died on October 3, 2009. Many of the 45 others who survived, including Carter, struggle with the guilt that they couldn't save more lives.

Yet Carter's daring efforts to rescue his fellow soldiers in the face of imminent death earned him the nation's highest military decoration, the Medal of Honor, which he will receive on Monday at a White House ceremony.