Trump also says he's bringing back the death penalty so he seems to be somewhat inconsistent.

It's not insane, it depends on what you value.

If you value societal order above all else, then you want extremely horrific punishments for crimes, you want near-absolute certainty that you'll be punished for criminal acts, and you want capture and trial to be swift, so that people know that breaking the law results in:

Swift capture Swift trial Swift execution

And with those three things, you get a highly ordered, law-abiding society, because it becomes common knowledge that breaking the law results in death, guaranteed, so unless you're just stupid or insane, you don't break the law.

If you don't value that kind of clockwork societal order, then you get... Western civilization.

Frankly I'll take the chaos of our Western civilization over the stifling draconian societal order of places like Singapore any day of the week.