I know this was a joke, but I still just going to put this out there.
North Korea against US? Aha..AHAha. AHAHAHA.
It's simple really. NK don't got stuff. They have a stockpile of 5-10 Nuclear Warheads. And yet to make a ICBM that can complete the 3 Stage Booster. North Korea also cannot make a warhead small enough to fit onto their Unha-3 or Taepodong-2 Intercontinental Ballistic Missile(ICBM). Like seriously. We have a stockpile of 5,000. Many of which are scattered around the globe in Ohio Class submarines (Trident II SLBM). And we have the Minuteman III ICBM.
And even without nuclear war.
We have a powerful military.
We have MQ-9 Reapers (UCAV), we have F-22 Rapter's (Stealth Air Superiority Fighter), Bombers, advanced Satellite imaging (Which North Korea cannot even get into space correctly), a navy with Aircraft Carriers, Destroyers, Etc. If I must go on. I will.