Thing is that Trump acting like a jerk towards China comes at a pretty bad time. Like, getting tough with China might have been plausible ten years ago, but China has been on a nationalistic tear lately in a way that is illogical and points to internal legitimacy problems. Which means that a stupid unnecessary war is more likely given current conditions than in the past. Like, the whole South China Sea thing is unnecessary, and it is not the United States changing the status quo like what happened with Ukraine and Georgia, but China changing the status quo. The Chinese have also been squabbling with Japan over the Senkaku islands which literally cannot support habitable life.