"The Star Spangled Banner" brings crowds to their feet, 200 years later

President Obama has proclaimed "National Flag Week" in honor of "the banner that weaves us together."

The flag that withstood the British bombardment at Fort McHenry in the War of 1812 still draws an audience at the Smithsonian, says curator Jennifer Jones.

"We have really looked at it as an iconic object of America," said Jones.

While the flag may be showing its age with eight feet worn away and one of its stars missing, the song it inspired has never been in better shape. Francis Scott Key wrote "The Star Spangled Banner" 200 years ago this year.

Brian McKnight performed "The Star Spangled Banner" at last year's NFL Pro Bowl.

"You listen to the lyrics that Francis Scott Key wrote and you are taken back to that night. If you can't feel that enough to sing it the way he wrote it, and to feel what he meant when he wrote it, and what it meant to everyone and what it meant for 200 years now, then you shouldn't be singing the song," McKnight told CBS News.

The song was made popular in 19th century patriotic social club and was first played at a World Series in 1918. "The Star Spangled Banner" became America's official national anthem when Congress chose it over "America the Beautiful" in 1931.

The song is notoriously difficult to perfect.

"Sometimes you'll hear someone start it and I'm like 'Oh, they started that a little high. Let's see what happens when they get down to bar 42,'" said McKnight.

The flag and song together have formed the fabric of a nation's identity.