It is only in the last 50 years or so that the "missionary" who only wants to help, not preach as well, has come forward. For the most part, I agree with Katlaughing. The "missionaries" who came with the conquerors to the Americas regarded heathenism as something to be uprooted. The mindset of the inquisition certainly came to Mexico. The material wealth and power of the conquerors were such that the natives were, in a real sense, innocent prey.
As an aside to your comments, Rick, some of the 19th C. preachers in Canada were extreme in beliefs. A Rev. McDougall (Wesleyan) who was active in what is now Alberta even regarded the Orthodox and Roman Catholic Ukrainians as benighted and fodder to be converted; a physician in his coterie combined McDougal's ideas with his medical treatments (unbelievably, some of the Ukrainians were converted). He and his group stole a sacred meteorite from the Cree in order to prevent its ceremonial veneration. It was shipped to the Wesleyan college in Ontario. It is now back in Alberta, but in Provincial storage. Some day, it may be returned to the Cree, but Canada has not yet followed the United States' legislated program of returning sacred objects to the tribes. Unfortunately, the majority here still regard McDougall as a great Canadian.