It is quite feasible that they really are meant to be a kind of deliberate p1ss-take. Not necessarily toward N. Korea, nor China etc but possibly to create further division and confusion on 'home turf' between his followers who like this kind of approach, and his detractors who do not.
There are theories as to why that divisiveness might be considered useful to Team Trump, but I'm not sure that it is quite panning out as they expect so far.