Trump doesn't say anything lightly. He will make big gestures and maybe a generalisation or two, but when it comes to the important things that could have MASSIVE consequences if proven wrong, he checks, double checks, triple checks.

You don't live in the public eye all your life without learning a few things about libel and slander. If you're going to accuse someone of something, make sure it's bulletproof. It makes for harder hitting insults too.