you may be able to influence by making sure they understand how human you are. There was a scene in Star Trek: The Next Generation where Riker had just shown surprise that Klingons laughed. A Klingon told Riker, "we love our children. We have parents. They look like us. We look like them." It was such simple language, but it really cut to the core of Riker's lack of having thought of all the ways his enemies are like him. Put your face out there for the ones who are capable of thinking this way.
But also learn to recognize a psychopath and don't waste your time on those people. You're in the middle of a job that's every bit about making sure there are people on their side who empathize with us on the most basic of human levels even if ideological empathizing is off the table. The Hail Mary Pass strategy to delay the worst is to slow down the "us vs. them" process and the techniques of appealing to humanity to accomplish that will be wasted on psychopaths. So, learn to recognize them and be careful because they spend their lives learning not to be recognized.