Nationalism decreases

Probability: 51%

Timeline: 50 years

This is a tough one, so I can only really give it slightly better than a 50/50 chance. So the astute among you may have realized this isn't really a very good prediction at all. More of just a comment.

Overall, the world's population has become a bit more "mixed up" as people move around. And people tend to acclimate to a country's culture given enough time.

There are a number of people that consider themselves "citizens of the world" and aren't overly nationalist.

But there are far more people that get extremely fired up about their patriotism. Enough to be violent about it.

Hopefully the "us versus them" mentality will subside as society progresses, but at current, it's still really just a hope.

International borders open up

Probability: 30%

Timeline: 50 years

This is more of a wish than a prediction.

It seems that all countries -- even the ones you'd traditionally consider to be "poor" -- are cracking down on immigration.

It is becoming increasing difficult to live and work in a country other than the one you happened to be born in.

People's movement is restricted by governments, and increasingly, corporations -- as working for a local company is often a requirement for residency.

Unfortunately, nationalism seems to be on the increase, and I don't foresee this happening in my lifetime.