^ I think if you remove the jingoism that clouds our judgement you might appreciate Holdfast's view under a more objective light. It is, in essence, a final, stable economic equilibrium state.
Attempting to maintain the status quo would surely doom those in second and third world countries to stay there, as they would be too far behind the curve to have any hope of catching up with the first world (which does include countries other than the US).
Nope, still a terrible idea. They need to build their economies for themselves not tear ours down.
It's not so much "tearing us down" as a matter of them integrating themselves into the global market, which WILL happen. As more things are able to cross borders, or work internationally, things will naturally level out. And those with viable skills will earn more, and those that are at the bottom of the barrel will find increased competition for low-skilled jobs.
Why should someone continue to pay you more for a job when someone else can and will do it for less? Only way to stay ahead in this one is to market ourselves as the higher-skilled workforce, and be the people inventing and developing the item rather than the one tightening the bolts or sweeping up after.