Christianity is Christ's teachings, and any other definition is a strawman. What you're talking about is man's sinful nature, and that is separate.
What I'd like to be talking about is the relationship between the Christian religion and Western imperialism and the consequences of Christian conquest on the narratives of history (specifically the narratives of groups oppressed by that religion.) What you're engaging in is pedantry and a gross application of what I'll call the True Christian fallacy. Fair enough. We can't have a conversation about this. Good night.
Your "No True Scotsman" variant just shows that you don't really grasp this idea. Ironically, what you're doing by making Christianity a grab-bag of bad behavior from people you don't like, instead of grounding it in a clear and unambiguous definition, is a clever perversion of this fallacy.