Sure but you could just nuke us too, given that the response to a mass civilian death event would be the same. Same reason the US would be foolish to destroy the Three Gorges Dam.
It doesn't need to be a mass civilian death event. They can wait, collect data and kill 90% of our most important soldiers, heads of state, spies and everyone needed to maintain critical sectors of our economy. They could kill everyone who is anti-china. They could kill all the members of one political party (any one) as a false flag and cause a civil war.
Surveillance technology is nessisarially selective, so these "all or nothing" hypotheticals do not apply.
Surveillance technology is nessisarially selective, so these "all or nothing" hypotheticals do not apply.
See also "slaughterbots". https://www.youtube.com/watch?v=O-2tpwW0kmU