Most notably, the ease of information exchange and transport of goods around the world. (and services, as anyone who's spoken with cust service knows) This levels the global markets, and along with that, global standards of living. China and India want cars, air-conditioning, and electricity 24 hours a day now too. Those who had is poor, are getting it better now. Those who had it better, (us) will inevitably decline in our SOL, if we want to remain competitive.
Didn't someone just post an article about US wages being too high? Fits right into his observations. NAFTA has accelerated the flattening of the world.