What is the national of the US?

Answer 1

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, through the perilous fight, O'er the ramparts we watched, were so gallantly streaming? And the rockets' red glare, the bombs bursting in air, Gave proof through the night that our flag was still there. O say, does that star-spangled banner yet wave O'er the land of the free and the home of the brave?
The Star Spangled Banner. Written by Francis Scott Key after witnessing British bombardment of Fort McHenry during the War of 1812
The Star Spangled Banner.
"The Star-Spangled Banner" is the National Anthem of USA.
That very much depends upon whom you are. The states of most nations have chosen "national" anthems.

The oldest such anthem is probably that of the Netherlands, "Het Wilhelmus", written about 1570.

Spain still has no "national" anthem.

The lyrics to the United States "national" anthem are taken from a poem by Francis Scott Key originally called "The Defense of Fort McHenry", sometimes called "The Siege of Fort McHenry", but the anthem itself is named "The Star-Spangled Banner". The tune is slightly modified from an English composition, "The Anacreontic Song". (For a while, Luxembourg used pretty much the same difficult tune for their anthem, but they abandoned it long before it became the official anthem of the United States.)