I think that President Trump's threats to North Korea are an attempt to trigger the assassination or overthrow of Kim Jong Un. Ironically, that is unlikely unless he loosens his grip on power.
I think that we should all be very, very concerned. North Korea may not have any real friends but China will not be happy if the US destroys, or takes over, a country on its doorstep. Also, since China has been building islands in the Philippines archipelago, China itself has been regarded by many as a clear and present danger to world peace.
Because of Western sanctions, Russia has been cosying up to China. If NK triggers a war, the US and it allies could be up against both China and Russia. A few years ago, it took Russia just 15 minutes to destroy the armoured divisions of the Ukrainian army. I doubt that any country with the exception of the USA would last much longer even in a conventional war. And since the war must be won at any cost, both sides would inevitably turn to nuclear weapons. For a variety of reasons, clean neutron bombs would not be regarded as sufficient.
Don't panic, though. Remember the old advice from the Cold War period, which went something like this:
1. Stay away from windows and glassware.
2. Loosen your tie and any restrictive clothing.
3. Empty your pockets of pens, pencils and any sharp objects.
4. Sit down.
5. Bend over and place your head between your legs, as you would prior to a 'plane crash.
6. Kiss your ass goodbye.
Or, as Bowser suggested, just
"Eat, drink and be merry - for tomorrow, you may not die after all!"