To me, the USA is EXTJ.
But more like S, i think.
This coming from my ( i guess) European beliefs that most americans are usually boastful of their grandness and usually not very kind towards other countries. Or kind, but in a self-seeking way.
I think we also see them as S because most people who appear on TV fit some kind of stereotype (jock, nerd, emo, that kind of thing). But their stereotypical diversion can be seen as N as well, so im unsure.
The J is just the feeling you get from them.
And the E is obvious.
... i don't really like America. I think you can tell. But it's all probably media induced so... it's complicated too.
How about Spain? ESFP maybe?
P.S- I'm an ignorant when it comes to USA's history, so i'm just rating for what i see on TV. I think EXTJ fits for the history too though.
And the country's not always similar to their leaders and decisions. America is made of it's people.
Against me, there's also this theory that says we can never have an exact notion of something so big as America's population, so our opinnions will always differ. Only if we individually meet every person will it be relevant, and that's impossible.
So... yeah, it's all relative and differing.
(This post was made in a rush, so you'll have to forgive any mistakes.)