In every human population there is a small percentage of people with some ideology that makes them inclined to do harm to others. 3700 anti-black incidents, 1100 anti-semitic, in the US - the population is about 300+ million. The hater-attacker percentage is something like 1 to 3 x 10^-5. That is tiny!

Of course it is deplorable that we have this much, and undoubtedly it implies a larger percentage who are hateful but not crazy enough to attack people. Still it does not seem a crisis. The situation has improved greatly in the US, I think other places have worse problems of this kind (e.g. see waps on this page).