Also lots of killers seek psychiatric help voluntarily (and are often sadly ignored). For a sane, moderately competent person it’s easy to plan the perfect murder or terror attack – it’s a different thing to carry it through because a sane person also has mental guardrails.
Mossad is effective because Israelis are ruthlessly trained to dehumanize anyone who’s an obstacle to their goals.
Gentoo is fun and a nice way to learn more about computers. Their wiki and their community was really good when I was into it, I’m sure it still is. But compiling everything from scratch is quite demanding of your CPU and your time, so it’s not really something that you run as your daily driver for long.