If it reaches the point that residents in Beijing get spooked, it would give China further motivation to cooperate. I think China is still jerking us around. The best they currently want to do is probably to make N. Korea temporarily freeze their missile and nuclear test, and forcing everybody to spin it as his victory and back off from N. Korea.
I think NEO plans to involve involuntary evacuation should start to take place. Another thing that would turn the Chinese shit white would if the State Department clearly advises NO US citizens to visit or stay in China’s northwest provinces such as Heilongjiang, etc., bordering North Korea. They don’t need to say “why”, just “go there.”