What's wrong with left wing nationalism? It's one of the many reasons I had been banned from reddit, I said one time that I leaned towards a national kind of socialism but I did not mean the nazis and I was banned immediately.
It just seems to me that being opposed to the idea of borders is a little crazy, I can't easily see the whole world somehow agreeing with the exact same ideology or governance, among many other potential flaws.
https://en.wikipedia.org/wiki/Left-wing_nationalism