I'm going to guess that a lot of people in the US, like myself, have been brought in on projects that were originally developed overseas--projects that we're in pretty sorry states when the product owners finally gave up and hired a US developer. While it is obvious that there must be many excellent developers from all over the world, I can still say that my experiences with non-US developers have not been good.

(note: Most of the reason for this is because US companies going overseas are primarily doing so to save money and probably are trying to cut more corners than they should.)