Here goes the popular story in highly condensed narration:

Each crab is perfectly capable of crawling out of the bucket and would do so if it was left alone in the same bucket. But presence of other crabs will ensure that it gets pulled down every time any one of them tries to start making his way out of the bucket. This story has been used as a metaphor countless times in motivational speeches where virtues of collaboration are highlighted.

And here is a time-lapsed version of European political history through the early modern ages (16th century to 19th century):

The simultaneous existence of major states viz. France, Spain, Austria, England, Germany, Netherlands, Italy with waning and waxing powers at different point of time practically prohibited emergence of a dominating force that China, Russia, Japan and India witnessed during the same time. This was an era of rapid technological developments (largely to gain an edge over warring neighbors) and thus always had a considerably higher probability of one specific invention catapulting the innovative state to become a continental superpower. However, that never happened. For about 4 centuries. It just did not.

Yes, at various points, it looked like one or the other state will rise to the top but in a baffling case of perennially shifting loyalties and germination of new coalitions, enemies of that state united to keep things in check. No one state ever could muster enough differential relative power for complete subjugation of its neighbors.

And yet, this story culminates (in 20th and 21st century) with continental Europe emerging as one of the most influential and powerful political and economic blocs in the world.

All the crabs, while checking each other, ensured that the bucket they were in sailed through the tough times and they all landed at the top of the world.

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