It's not necessarily 'irrational'. A 51% miner could profit from Bitcoin's downfall, or by threatening others, or even by bluffing an attack. See, e.g., the Gol

It's not necessarily 'irrational'. A 51% miner could profit from Bitcoin's downfall, or by threatening others, or even by bluffing an attack. See, e.g., the Goldfinger Attack in https://www.cs.princeton.edu/~kroll/papers/weis13_bitcoin.pdf https://www.cs.princeton.edu/~kroll/papers/weis13_bitcoin.pd....