Unless the US dramatically improves its educational system, India and China will eat the US alive over the longer term, unless the US is able to continue to import the best and the brightest, which might become increasingly difficult as wage levels narrow for such talent. The rest of the planet is a distraction, irritating sometime, but in the end rather irrelevant as to this issue. Europe has decided more of less to commit demographic suicide. It's headed to theme park status.
Yet another reason I consider Torie one of the smartest people here. Though props to Dead for naming Russia first. There is much merit in what he says. But yeah -- the China/India economic surge should worry us.
Of course, we ignore ANY other country at our peril. Brazil, Venezuela, any of the major players in Africa -- all of them have some bearing on our future. But the OP asked for the greatest potential threat. And Torie knocked it outta the park.
