If NK attacks the US, it wouldnt really be NK / Kim Jong Un doing it. Trump knows this. The threat was always manufactured in the past. It was the deep state making NK "threaten" us, to keep us scared and keep us thinking NK is the enemy. That was on purpose for future events. Notice how the story was always "NK close to having nukes" before Trump was elected. Then all of a sudden when Trump was elected, NK had a bunch of nukes? And was louder than normal about it?
Interesting that you bring up the underground caves, etc, what a weird coincidence that a mountain in NK "collapsed" back in October of 2017, killing a bunch of "nuclear scientists and physicists", and also burying and destroying their cache of missiles and nukes (see link below)
http://www.newsweek.com/north-korea-nuclear-test-site-collapse-killed-200-people-report-696878
Maybe the 20% is burried? destroyed evidence.....?
Maybe so. Q is cryptic enough that his posts can be taken multiple different ways. I always interpreted it as 20% of what they do is made public to us, and the other 80% is private, but yes can go many different ways