[Uhuhreally]

easy. Imagine twin brothers each with identical wealth and then one of them steals the other one's money. Now one has twice the wealth of the other.

[fastball]

If my brother stole from me, I'd steal it back. If that failed, I could always kill him. Why couldn't the colonized do the same?

The Europeans succeeded in their colonization efforts because they were more technologically advanced than anyone they were colonizing. It is not a case of twin brothers. It is the case of an older brother stealing from his baby brother.