Scott,
I meant it in the sense of how the U.S. PGA Tour has been perceived around the world. Almost every great international player has wanted to play in the U.S. in order to measure their own skills. Like it or not, since Bobby Jones day there has been an unbroken string of Americans considered as the best player in the world (Jones, Nelson, Hogan, Palmer, Nicklaus, Woods...)
There have always been great players outside of the U.S., just not enough of them in one place to offset the size, numbers, money & media exposure as enjoyed in the U.S.