score:8
Given the US Embassy in Madrid FAQ and the previous experience my wife had past December coming back from Barcelona it is a no.
The flights from Spain and especially from Barcelona are almost universally go through agriculture control at US customs (at least the case in JFK and Newark) specifically looking for Jamon.
The only possible exception might be vacuum packed sliced Jamon but again from my wife's experience with agriculture control in Newark I would say it may be a 50/50 proposition at best.
Upvote:2
Donβt even try the vacuum pack. I read this post, tried, and was confiscated at customs. The answer is a clear no.