Robert Day joined the U.S. Marine Corps just a few months after the 9/11 terrorist attacks. Soon he was being transformed into a Marine at Parris Island, and, less than three years later, he would be part of some of the most intense combat of the Iraq War during the Second Battle of Fallujah in November and December 2004. He served as a machine gunner with the 1st Battlion/8th Marines.

In this edition of "Veterans Chronicles," Sgt. Day takes on a quiet first deployment to Iraq, into the much more intense training for the second tour in Iraq, and into the gritty details of the urban combat in Fallujah when his platoon returned to the war.

Day explains the tactical approach in Fallujah, what it was like firing at the enemy while being fired upon, his role during the house-to-house combat throughout Fallujah, the mindset needed for a relentlessly intense battle that raged for weeks, and how his platoon dealt with the loss of one of its most beloved members.

It's a fascinating, detailed, and candid account of some of the toughest fighting of the Iraq War.