The flag and the meaning behind the stars and stripes, the Statue of Liberty, American football, and the other images that stand in for the United States.
Every country has a set of images that do the work of explaining it, and for the United States the set is short and very familiar: the flag, the Statue of Liberty, football. The video takes them one at a time and says what each actually means - what the stars stand for and what the stripes stand for, why the statue is where it is, why one sport carries so much of the national identity.
That makes it a geography and history lesson as much as a vocabulary one, and useful beyond the classroom - for travellers as much as for ESL students. Two and a half minutes, clear visuals, and it goes well before any lesson on American holidays.