Russian tanks rolling into Hungary and Czechoslovakia is more provocative than Russia attacking Ukraine. And if you really think that Ukraine and Russia is where world war I and world war II started, I really can't help you.Difference between this and any event you just mentioned is that it's factually the largest military offensive in Europe since WW2. If you can find one bigger, I'd be happy to correct myself.
This is also the same general region that kicked off the past 2 World Wars.