You said that he didn't kill anyone because he got caught first. Which implies that if he didn't get caught he would have actually killed someone.

They really aren't the same. It's a common fallacy on the Internet to lunge straight to the worst possible case and equate that to whatever it is you're arguing, but it really isn't the same. Sure, the secret service won't ignore you if you say you'd like to shoot the president. But will their reaction be the same as if you've smuggled a gun in to a press conference and are spotted actively moving to get near him? Obviously not, because what I said remains true. Simply saying "I'm gonna kill you" is not the same as actually trying to kill you.