Among the hundreds honored were victims of extremist attacks, fallen soldiers, long-serving politicians and such celebrities as baseball legend Yogi Berra.
Those honored last year alone with a half-staff U.S. flag include five Georgia Southern University nursing students killed in a car wreck and a Downey, California, police officer shot in his car in a police parking lot in an alleged robbery attempt. Flags were lowered for a Missouri state official who was running for governor when he killed himself after a radio ad mocked his appearance, and for an Oklahoma state road worker who died helping to fill a sinkhole. One honoree was a police dog shot in Ohio.
Who gets honored, and when, can be controversial. Recent years saw tension over lowering flags nationwide for former South African President Nelson Mandela and in New Jersey for the Grammy-winning Whitney Houston .
Seeing half-staff flags on July Fourth last year jarred Amherst, Massachusetts, resident Larry Kelley, who felt the tribute — part of a 13-day honor for a state senator — "sends the wrong message" on the nation's birthday.
"It just seemed to me to take away from the whole idea of lowering the flag," said Kelley, adding that he'd have felt differently if the state were mourning a line-of-duty death or major public trauma. He initially didn't even realize what the occasion was, until a reader of his local-issues blog filled him in.