Or they could just muster the resources and do it anyway, with no warning.
No unusual mining power growth can escape people's attention, you get the most paranoid bunch of guys in the world here, why bother with additional resources?
And it's not even relevant, any prevention against 51% attack has to be implemented such that it's effective against all possible 51% attacks(which you have to do anyway if you can), to just target a particular group of people is ridiculous.
They would do it as closely together as possible. They're unlikely to connect one machine at a time to the network.
It's an example of a nation. But yes, it could be
any nation with enough resources.
Exactly, so it's not related to how many nodes are, or even how much hashpower is in China, right?
Not to say a 51% attack can only be pulled off by a single node with 51% of the hashing power, not a lot of nodes combined together.
So what OP said is not relevant.
I spoke of "other ways", the fact is that even China tries to play fairly, with its cheap mid-level skilled labor and supply chain and cheap electricity, no other nation in the world can match it in mining capability.