Being "alarmed" does NOT mean running around like a chicken without  a head. It's being aware of danger within your area. It means being alert and vigilant anytime you go out in the public. Come on Bloomberg News! Bashing Trump for this is nonsense!! Londoners have reasons to be concerned. 3 terrorist incidents in a couple months  would cause "alarm" for our great nation. 
All you guys gotta stop with the hate and realize that the President gets thing right sometimes and this is one of them.