The US sends planes by them all the time too. Each are checking out the other. Mind games, but not to the bad extend thet Kim in N. Korea does. They film take tons of pics and compare to the earlier ones for visable upgrades made. The Satellites provide even better coverage. Both have them too.
I think the N. Korea is the one to worry about. That fuse was lit some time ago in the Obama admin but it's getting very short.
China is the joker in that deck of cards. If Trump has them on our side sanctioning them as has been said with coal and other necessities thay can't get elsewhere, it may be cause for Kim to do one of tow things, either cut back & do as countries hope for or cause him totally loose it & do more that will cause a serious escalation in this.
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