For better or worse, their civilian lives were forged on the battlefields of Afghanistan, say Marine veterans. For some veterans - even one who lost a leg -- the war was a defining, motivating experience they wouldn't trade. Others, however, are struggling because of the war they fought. Scott Pelley meets both in his story about veterans of a Marine company that took especially high casualties in Afghanistan. Pelley's report on men who served in Golf Company, 2nd Battalion,