Earlier quoted context omitted.
I'm never sure if Theresa May is evil or incompetent. It may be she is just incapable of controlling her department, although perhaps I'm being too charitable.
I strongly suspect it's the latter - every MP who becomes home secretary basically turns into a fascist, almost overnight. I guess they show them a bunch of secret reports on events that "almost" happened to scare them into going along with whatever the Home Office civil service have always been wanting to do.
Assuming that's reasonably accurate, it is hard to imagine how spending half your day every day just reading about people who are probably the worst of the worst in many cases could not have a profound effect on how you view the world.
Whether anyone so deeply immersed in such a biased view should be expected to serve in such a position for more than a short period of time, and whether they should be responsible for making judgements about much of anything else during that period, are entirely different questions.