Limiting the view to the relatively short time of the #Crusades and the conquest of the Americas by Europeans is a very limited view.
In the first centuries after the death of Christ, Christianity spread throughout the "known world" of the #RomanEmpire peacefully, in fact the members of the sect often being persecuted by the authorities.
In fact, the picture you show of a #crusader has a reason. The military...
...expansionism of islam and the conquest of the #HolyLand, which had belonged to the #Roman and then its heir, the #ByzantineEmpire, by invading #Arab forces, expanding throughout the #Mediterranean and beyond.
So, the crusader picture does not really support your story.
What you are saying would be true for large parts of #LatinAmerica, though.
...as a way to control the subjects of a ruling elite is something that has been done throughout human history and is certainly not limited to the Christian and Islamic faith.
It might despicable from a moral point of view, but it is a very powerful tool from a strategic point of view and will therefore continue to be (ab)used in the politics of power.