You mean a conventional attack? It would be met with overwhelming conventional force and the invading Chinese forces would be destroyed. Russia's problem is that the same scenario for them would end even worse, since they are so weak in conventional terms that even a small regional power like Turkey could destroy them, and the US could do so without even breaking a sweat. So their choice is simple: give up the island, or get turned into glass?
Imagine believing that Russia is gonna turn itself into a glass crater for Wrangel Island.
What would happen if China mounted a successful attack on Hawai?
You mean a conventional attack? It would be met with overwhelming conventional force and the invading Chinese forces would be destroyed. Russia's problem is that the same scenario for them would end even worse, since they are so weak in conventional terms that even a small regional power like Turkey could destroy them, and the US could do so without even breaking a sweat. So their choice is simple: give up the island, or get turned into glass?