This was actually really popular in Communist regimes, which often went to random tribes in Central Asia and the Balkans and went "okay, you're in the xx ethnicity now, you're in the xx ethnicity now" and half the time those ethnicities were made-up on the spot. It was a well-intentioned but ultimately really stupid policy that ended up pretty poorly for my family, which is why we're stuck in Obama's America. Except we're trying it here now too.
I must admit that I'm not an expert on ethnic politics in America, but I'm pretty sure that Stalin's almost random line drawing in Central Asia is a fair bit different to whatever is happening in America. I'm not an expert on the region (did a course on Central Asian International Politics when I was at uni, found it incredibly interesting) but there you had a predominantly nomadic population forced to assimilate into a few "nations" (that were vaguely based on history, although the borders were basically done by Stalin to make them weak) and them subjected to 50+ years of Russification to a much greater extent than the European Soviet Republics, while in America you have a policy that's more focused on integration which is a much better policy than assimilation is. Sure grouping people from East Asia and South Asia together as being the same is silly because both are very different places, but its not like there's an organised government policy to try and combine two different ethnic groups into one.
I assume that when you're talking about the Balkans that you are primarily referring to the former Yugoslav countries, and the ethnic troubles there were not based on Tito or any Communist leader randomly splitting groups up - the borders of most Balkan countries (Kosovo and Serbia are the main exceptions) are basically identical to the internal boundaries of Yugoslavia when it was created in 1918. I'd personally argue that Tito did very well in preventing ethnic troubles in Yugoslavia when he was alive, and that its no coincidence that Milosevic's moves towards a more unitary state led to the whole thing collapsing in an incredibly tragic way.
This is very off topic though, it has nothing to do with Donald Trump really