The U.S. Army’s Second Brigade of the Third Infantry Division was part of the force that invaded Iraq in March of 2003.  It raced out of Kuwait in Abrams tanks and Bradley fighting vehicles across open terrain, fighting a battle for which they'd trained. Mechanized infantry combined with the tank sledgehammer brushed aside any resistance losing more vehicles to maintenance than enemy action.  Things and the plan changed when the Second Brigade made it to Baghdad.  Instead of encircling the city of seven million people and trying to clear it block by block with dismounted infantry, the decision was made to make a rapier armored thrust into Baghdad, seize the centers of power, and cause Saddam Hussein’s regime to collapse from within.  That is what the Second Brigade did and what is chronicled in David Zucchino’s “Thunder Run: The Armored Strike to Capture Baghdad.”