Copy and paste to follow, not opposing your statemet just find it interesting :https://www.statista.com/statistics/1200477/bitcoin-mining-by-country/
It's very simple, they just take control of the mining power. They will absolutely already have explored ways to weaponise various blockchains, if it ever becomes useful and not just a way for people to try and flip tokens for profit.
It's a glaring security issue. There's nothing to stop China saying nope, we're not using BTC. But we're going to control the network. Enjoy!
With Bitcoin, staging a 51% attack on the network is seemingly unlikely, simply due to the size of the network and its hash rate. One estimate puts the cost of running a 51% attack on Bitcoin at just over 15 billion USD. Many altcoins, however, are much more at risk. All it takes is sufficient rented mining equipment that doesn’t need to be kept in-house and a relatively large initial investment. It was for these factors Ethereum Classic was hacked and hackers stole the equivalent of more than 1 million USD of its native cryptocurrency. The overall network hash rate just doesn’t match up to Bitcoin’s.
With Bitcoin, staging a 51% attack on the network is seemingly unlikely, simply due to the size of the network and its hash rate. One estimate puts the cost of running a 51% attack on Bitcoin at just over 15 billion USD. Many altcoins, however, are much more at risk. All it takes is sufficient rented mining equipment that doesn’t need to be kept in-house and a relatively large initial investment. It was for these factors Ethereum Classic was hacked and hackers stole the equivalent of more than 1 million USD of its native cryptocurrency. The overall network hash rate just doesn’t match up to Bitcoin’s.
Whole article here
https://www.bitpanda.com/academy/en/lessons/what-is-a-51-attack-and-how-is-it-prevented/