2000AD often predicts the future, and is the current world political situation similar to the 'Block Wars' of Mega-City One, but on a gigantic continental scale? America forms one block, Europe another, Russia a third, China a fourth and India plus Japan a Fifth block, all competing against one another for power, influence and resources. Are we now in a period of competition with blocks cooperating with other unions to undermine a third rival group? Australia, Japan and India work together against China's rising Pacific power, say as one possible example. Was Judge Dredd right in its prediction, and 'Block War, Man!' is the grim reality we face now?
Let's just hope that none of the blocks decide to start dropping 2 cred freeziwhips.
I think we've already had Block Wars in the way you imagine, for example the struggle against Hitler Block.
To my mind, the closest thing to "Blocks" would be the ancient Greek city states fighting amongst themselves as in the Peloponnesian War between Athens (Block) and Sparta (Block).
Its all a bit Orwellian... even down to the doublespeak.