I probably would have shrugged off the phone call if that’s where it ended.
The follow-ups, with Trump on Twitter and the Chinese publishing a threatening front page editorial in the People’s Daily, made me more concerned.
It’s still rhetoric. No need to exaggerate what happened. However, my concern is that it will continue in this direction, and both leaders will put themselves in a position where they have to take tough-looking actions for the sake of acting tough in front of domestic audiences.
I don’t dispute your assessment of China’s national interests. But while the unitary actor assumption is useful to identify national interests and incentives, it’s not uncommon for states to act against those national interests, to take on greater costs at the international level, due to domestic political pressures.
There are many actions the United States could take that would signal a tougher position in the South China Sea while avoiding the domestic audience trap. Repairing the relationship with the Philippines and conducting joint naval exercises should be high on the list.