Compare the impacts of the conquest of the Americas by Europeans and the conquest of Central Asia/Middle East by the Mongols vs the European conquest of Egypt. The conquest of Egypt, while colonialism, seems almost benign in comparison to the destruction brought about the former two examples.
The conquest of the Americas killed more than 90% of the population of the Americas. The conquest of Egypt mentioned before maybe killed 1% of the population. Are they the same thing or not?
In any regard, the last century has been the greatest disaster of conquests in terms of absolute numbers/victims/weapons used/etc.
When you know the full history of the Conquistadors and their relationship with the local population, things are not so clear.
For example, the Spanish:
- didn't teach locals to do mass ritual sacrifice and throw the bodies down the steps of the temples
- didn't tell one of the local kings to burn his empire's library to erase any history before his reign
- didn't force their "local allies" to march on the capitals of the empires.