I'm not sure it would have that effect. Such an action from China would almost certainly result in solidarity and coordinated action from basically the entire

I'm not sure it would have that effect. Such an action from China would almost certainly result in solidarity and coordinated action from basically the entire West. If others don't act, they're next. I also don't see how a US response is somehow an attack on free market values. Dumping $1.2T of Treasuries onto the open market is not normal market activity. It's an attempt to manipulate and distort the market. China wants to surpass the US, but while such a stunt might harm the US, it would do immense damage to China. I think it would be more like a striking blow alienating China from much of the global economy and financial system for a long time to come. That is surely not the route to surpassing the US as the preeminent world power.