On December 7, 1941, the United States was attacked by the Empire of Japan at Pearl Harbor, Hawaii. Then-president Franklin Delano Roosevelt decried the sneak attack, which drew the United States into World War II, and declared December 7 "a date which will live in infamy." Many Americans use December 7 -- called Pearl Harbor Day -- to memorialize those who lost their lives in the attack.

Half-Staff Sunrise to Sunset

The U.S. flag should be flown at half-staff from sunrise to sunset on December 7. To fly a flag at half-staff, raise the flag briskly to the top of the flagpole before lowering it halfway. To retrieve the flag, raise the flag back to the top of the pole before lowering it. All other flags flown -- such as state or organizational flags --should be flown at half-staff or removed. Those who display U.S. flags which cannot be flown at half-staff may instead attach a black ribbon the length of the flag and the width of one of the U.S. flag's stripes directly above the flag on the flagpole.