There's anarchy and there's anarchy.
And the future is nowhere near as certain as most like to think. What do you imagine will happen to the concept of globalization in twenty years, when we completely run out of fossil fuels? Barring some deus ex machina like fusion, that's basically the end of any society that extends beyond covered-wagon distance (and that only in the places that still have horses or other pack animals). Fuel cells require oil to produce, as do most other alternative power sources (barring low-wattage sources like solar and some very primitive versions of wind power, which could be rigged up by clever individuals to yield enough to operate basic industries and maybe even keep the lights going, no more).
How about all those nukes scattered across the still-Balkanized East European nations? It'd be foolish to assume they aren't ever gonna go anywhere, and a well-placed tactical nuclear warhead would put an end to the sort of politics you and I are so familiar with instantly.
Globalization is inevitable if you assume that the US will remain the oligarchic corporate republic it is today for at least fifty more years, and will maintain total international supremacy over that entire span. Anything less, and the globalist movement will fail.
Centralized government, of course, would be a tougher nut to crack. We'll pretty much always have it, it's human nature to seek power and so long as we seek it the stronger force in any society will always find a way to obtain it. Aside from a few very small communes and (supposedly) some of the experimental arcologies, and maybe Athens if one is generous with the term, there's never been a self-sufficient decentralized government. And since that's the real target of the anarchic movement, yeah, it's a bit of an idealist movement. But what's wrong with idealism?
