No, we are NOT going to pre-emptively hit NoKo. Literally every single one of his generals and military advisors - not to mention anybody with any kind of knowledge on the subject knows that.
Do yourselves a favor and google the subject a bit; Day One of conflict with NoKo - no matter who starts it - is a complete massacre - in their favor. Focking Seoul would be a GD memory.
Yeah, long term we win. The tide turns our way the longer we're at war. However, day one through five? Holy Chiit, hundreds of thousands dead. Why do you think SoKo can't stand Trump? "Hey great, diickface, talk tough - WE'RE the ones who'll be annihilated on day one. You can fight over the embers. "
Seriously, educate yourselves. The number of weps trained on Seoul/SoKo for a simultaneous, massive attack is incredible. Short of launching every nuke we can place in the region (thus killing SoKo and bringing in China), no way we can take all that chit out before they inflict massive casualties.