It's kind of scary how they convinced themselves that everyone is going after them, they act up and justify it in this exact way (a tranny school shooter thinks of himself as a hero who stood up to transphobic Christians for example), people rightfully call them out for acting out, they use those examples of people criticizing them as proof that "everyone is going after them" which fuels even more tranny shooters.
Also this persecution complex fuels it even more because if you genuinely believe this you will be even more likely to go out and murder people because you are convinced that "there is no other way"