United States, Canada, Mexico, Panama...

Do kids still say "Indian Giver" nowadays when their friend has given them something and they now want it back? The term is pretty ironic considering it was the US who kept taking the Indians' land, then giving bits of it back only to take it away again. Newspeak, perhaps. War is peace and all of that.
Then there's the Chinese fire drill - where your car stops at a light and everybody gets out, switches seats, and then gets back in. Where on earth did that get its name? In England there are "Chinese whispers," a term which means the same thing as "telephone game" in American English.
Kids don't sit Indian style anymore, according to my teacher friends. They sit criss-cross applesauce. Criss-cross I get. Applesauce? That strikes me as messy.
People before my time used to say things like "That's mighty white of you," to mean "that was nice, thanks." This probably isn't race-related however. We think that the term referred to the fact that in old Westerns, the good guys wore white and the bad guys wore black.
There's "Mexican standoff" meaning stalemate, but I've got no idea what's Mexican about it.
To get one's Irish up is to lose one's temper, which apparently my countrymen are known to do (though I've never done such a thing). I've heard that the paddy wagon is so-called because they used to need it to round up all the Irish folk (Paddy being a derogatory term for Irishman) when the bars closed. It's more likely, however, that the paddy wagon is so named because so many Irishmen were cops.
I wonder how soon, if ever, this stuff will fade.