This is the 70th anniversary of D-Day ... June 6, 1944. We all have seen the photographs and footage from the beaches of Normandy. We have seen the rows upon rows of our nearly 9,400 military dead at the Normandy American Cemetery - most of them killed in Operation Overlord, the code name for the Allies' invasion of France. But so few of us in subsequent generations can even imagine what author Rick Atkinson vividly re-creates in his epic book, 'The Guns at Last Light.'