You're thinking in short, next twenty years or so. A resurgence of nationalism is a response to globalization, but unless we give up our ways of living entirely (no capitalism, no markets, no growth) these movements will have practically no effect. Mass media alone ensure that, let alone the nature of global trading and social mobility. Think about the next two hundred years and there is no way culture on earth will not be vastly homogeneous. Whether that's good or bad I will leave open, my personal view is that all massive shifts in human development are accompanied by positive and negative effects.
I suspect the drawdown of easily-accessible, dense, cheap fossil fuels will spell the end of global integration; consider a very low-energy future where most communication takes place via radio and travel for 99% takes place at a fraction of today's rate. We would expect regional differences to increase as groups adapt to local areas, ideally while carrying out extensive sharing of e.g. practices and techniques.
Humanity is scientifically and materialistically closer and that will certainly continue, but the world is not closer in terms of modes of governance or ideas of how society ought to be organised.
On the contrary, 30 years ago after the fall of the Soviet Union that sentiment peaked and Fukuyama's end of history seemed plausible. Today with the nationalisation of cyberspace, we can see countless of new divides.
The US is rapidly withdrawing from global affairs, China is emerging with a competitive, alternative mode of organisation, a distinct European identity is beginning to form as a response to this particular in France, India is slowly emerging (see the very thread we're in), and Africa is a whole other matter.
But by no means does it look like the world is converging, as it did in the 90s and early 00s when we were all listening to corporate world music and cheering for Blair.