the meaning of the national antham

A friend of mine at work said today that on his way home yesterday he heard the Star Spangled Banner on the radio. He said that for the first time he understood it on an emotional level. For the first time he understood what it means to be be an American. He said he cried.

Oh, say can you see by the dawn’s early light
What so proudly we hailed at the twilight’s last gleaming?
Whose broad stripes and bright stars thru the perilous fight,
O’er the ramparts we watched were so gallantly streaming?
And the rocket’s red glare, the bombs bursting in air,
Gave proof through the night that our flag was still there.
Oh, say does that star-spangled banner yet wave
O’er the land of the free and the home of the brave?