The scary part about terrorism nowadays is they don't need automatic guns or bombs to do such attacks.
Attacks in Nice and Berlin showed as long as they are able to drive and have access to a truck/car to do that. I've read recently that ISIS used to ask their new recruits to come to Syria for full trainings but now that truck attacks are working for them, terrorists are asked to stay wherever they are and wait for their signal/turn. I am thinking ways how this can be prevented but can not come up with answers.