Of course not all, but many people are very racist against whites, and thus against anything that was/is predominantly caused or done by mostly whites.
For instance, slavery was common in Africa in the 1400s, and only brought to the Americas because slave owners in Africa were willing to sell their fellow black brothers to Europeans (who happened to be on their way to India to buy pepper). When blacks owned black slaves, that is to be ignored, but when whites owned them, that was an atrocity to be continually harped on and denounced to this day--according to the anti-white racists of today.
As Mohammed Ali said after his first trip to Africa, "Thank God my granddaddy got on that boat". He recognized that as bad as slavery was in antebellum America, it has been far outweighed by the good that Europeans have brought to Africa and the Africans such as improved farming techniques that have put food in the mouths of Africans who in the past would have simply starved to death. The continent of Africa is a land of vast natural resources that just sat in the ground for centuries, until Europeans came along and showed the Africans how to extract them, and use that wealth to turn their backwater mud hut villages into thriving modern metropolitan cities.
After WW2, devastated Japan and Germany were treated as colonies for a few years by a mostly white America. Now they are among the leading economic powers in the world. If any third world country leaders gave a hoot about their people, they would beg America to come in and colonize them, and even ask that they be added as a state.