In the scenario I'm describing, the attacker profits when the value of bitcoin tanks. Two new developments: - Vast investment in mining hardware due to the bu

In the scenario I'm describing, the attacker profits when the value of bitcoin tanks. Two new developments: - Vast investment in mining hardware due to the bubble. - Liquid BTC markets, including futures and shorting. Say that the world's miners accumulate so much hardware that it costs $1m / hour in electricity to run it all. At current prices, they'd still be making a profit! But if that changes, datacenters in China will go dark, BTC difficulty will go down, lots of hardware will sit unused. So if one group ever finds itself sitting on a ton of no-longer-profitable mining hardware, they could take a large short position and then attack the network.