World War II veterans looked back to 56 years ago and others paused to honor them Tuesday as crowds celebrated the opening of the National D-Day Museum. Hundreds came early to the Superdome to watch fellow veterans parade past as the museum officially opened on the 56th anniversary of the invasion to liberate Europe from Nazi terror. The opening of the museum has put the limelight back on World War II veterans. About 10,000 of them - including eight who wear the Medal of Honor - gathered here for four days of ceremonies.