The Language of Flags (Star-Spangled Banners)

The huge, tattered flag that inspired the lyrics of "The Star Spangled Banner" (the US National Anthem) is indeed a "star attraction" at the National Museum of American History (the screenshot above is a detail from a page on the online "Star Spangled Banner" exhibition). The huge flag on display was flown over Fort McHenry and survived the War of 1812, and it bears 15 stars and 15 stripes - representing the 13 original colonies, plus the 2 additional states (Kentucky and Vermont) that had joined the Union by that time. (The original plan was to keep adding 1 star and stripe for each new state that was admitted, but at some point this became too unwieldy and the number of stripes was "fixed" at 13.)

This website (as of September 2010) indicates that there's a Spanish translation of the anthem lyrics on display alongside the flag. (Note that this is NOT the same as the Spanish version that made the news back in 2006 - listen to the story here.)

Another intriguing version of the US flag in the NMAH is this Civil War era banner: the regimental colors of the 84th Infantry, 1866. This regiment was formed from the Corps d'Afrique of Louisiana, comprising of free black soldiers who fought for the Union. Note the French-derived place names on the red stripes (you can read more about this flag here and here). Interestingly, the writing in this flag is "backwards" - it reads left to right with the blue part (canton) on the right. As I understand it, the flag is typically flown facing the other direction (with canton on left).

A more stylized version of the "backwards" flag can be seen on this sign outside Newseum during Obama's inauguration in January 2009. (The number refers to Obama as the 44th President of the US.)

These versions of the US flag were displayed on the east façade of the Capitol when Obama was inaugurated in January 2009. The flags on the outside are the original stars and stripes (13 stars in a ring). The flag in the center is the current flag (50 stars). The other flags have 21 stars: this what the US flag looked like just after Illinois (Obama's home state) entered the Union in 1818.

As is the case with other flags, the "Star-Spangled Banner" is sometimes modified in order to make a political message. See, for instance, the protest flags here and here.