Just because its existed for only 80 years doesn't change the fact that Europe admirrably did find a way to settle mutual hostilities and create the degree of integration that we see today in the EU. It may not be perfect, but better compared to Asia, where Koreans and Vietnamese are willing to throw fists if anyone suggests that the way they used Chinese characters or celebrate Lunar New Year has any historical relation to China. It really does come down to history, since Europe was ruined by two World Wars driven by nationalism, while in Asia nationalism is what preserved culture and spurred revolutionary movements during colonialism. It persists today as China and Vietnam are still developing, while Korea despite being 1st world was still a poor country up until the 70s, and while the EU is politically united most Asian nations have their own interests.
But I guess for Europe after WW2 it helped the continent's hegemon became a country an ocean away, while for East Asia China is the most obvious candidate for hegemon. For everyone's sake, let's hope there won't be a regional war the same way Europe experienced one, but that means that even the playing field in terms of development is level the East Asian mindset will continue being one of eternal bickering.