Many analysts argue that Trump's missile raid on a Syrian air force field actually sends a stronger message to North Korea and Iran. Their point - if this president says he's fed up with something your nation is doing, the realistic result could be fire and destruction from the skies.
We've just spent 8 years with a president who might send an armed drone or a Seal team to take out a terrorists' compound, or kill a Taliban leader. Basically all parties in Syria, Iran, North Korea, and Russia ignored him.
The new regime is different. How different? That we will learn in due course. As President Trump is fond of saying, I'll tell you about military actions after they happen. There is real advantage in others not being certain how violently you'll react.
Can Kim Jong Il be certain we won't drop a tactical nuke on Pyongyang during some public ceremony where he presides? Kim is less certain of that today than he was yesterday. Ditto, the Angry Ayatollahs in Tehran.