A Utopia?
Never will happen, there will always be problems (that being said, there's something to be said for aiming high and landing slightly lower...there's no harm at all in wanting to create an As-Good-As-Humanly-Possible-topia.)
Socialism?
I don't feel it works, or communism...at best, they're fatally flawed fool's paradises, at worst, a system susceptible to corruption--see: "Animal Farm," an absolute masterpiece of fiction, and the perfect counterpoint to how the communal paradise is doomed to failure--as well as encouraging a sense of mediocrity.
A World State?
At some point in the future, I think it's inevitable, as we grow more and more globalized...but I'm not sure if it will occur in my lifetime, we're so divided...as to whether or not it would be good?
At the beginning...possibly not...in the end, assuming we survive that long, however, I think it could prove to be a beautiful thing...but then, this is me speculating 200 years down the road--and I'd never have guessed in 1812 that man would one day walk on the moon, build weapons with more destructive power than the sun, murder millions upon millions of its own kind in concentrated horrors untold, and invent the devices necessary for the Internet.
So, in 200 years...who knows.