December 7 of each year is National Pearl Harbor Remembrance Day. National Pearl Harbor Remembrance Day is also referred to as Pearl Harbor Remembrance Day or Pearl Harbor Day. It is a tradition to fly the Flag of the United States at half-staff until sunset in honor of dead patriots.
On Sunday morning, December 7, 1941 America's naval base at Pearl Harbor, Hawaii was attacked by aircraft and submarines of the Imperial Japanese Navy, killing 2,403 American military personnel and civilians and injuring 1,178 others. The attack sank four U.S. Navy battleships and damaged four more. It also damaged or sank three cruisers, three destroyers, and one minelayer. Aircraft losses were 188 destroyed and 159 damaged. The day after the attack, the United States declared war on Japan and entered World War II.
That is the USS Arizona sitting below the water. It is a graveyard/cemetery for the majority of those killed at Pearl Harbor. Above ship is the memorial for those lost.