What are some potential scenarios that a state actor can harm bitcoin if they control more than 51% of the hashing power?
There may be a lot of miners in China, but the People's Republic of China do not control the mining power.

A 51% attack on Bitcoin may be theoretically possible, but it is definitely not feasible. Andreas Antonopoulos addressed this question and answers it better than I could. Here's a video of this Q&amp;A: https://youtu.be/yWTQgmCuiCw?t=8