The real scary thing to me about these types of threats in the world today is the fact that these monsters don't seem to care if they get killed.
The common link to most of them is they go on a type of suicide mission. Whether they blow themselves up or expect to get shot by a cop the link is they don't care if they die. And that is the part that makes this threat today so unique and difficult to deal with.
I liken it to the Kamikaze attacks that occurred in WWII. Humans trying to cause as much destruction as possible and knowing they would likely die in the process. It was a new phenomenem that the military had to deal with.
Different in some ways but similar in some ways too.
https://en.wikipedia.org/wiki/Kamikaze
And today that sort of threat has surfaced again with these monsters. Combatting it is very difficult but we must do everything possible to try to identify and stop anybody thinking of doing such a thing.
Which means to me that special measures must take place by homeland security, LE, FBI, governments, and all other countries too.
It is a world wide threat to humanity as we have seen these killings occur in many places throughout the world.
We do know a lot of them have been stopped but obviously so much more work has to be done to stop the next idiot who doesnt care about his life. Such selfish souls.