6.9 Million BTC — Including Satoshi's — Are Already Exposed to Quantum Attack, and Bitcoin Has No Plan!

Roughly 6.9 million bitcoin — about one-third of all coins ever mined — sit in wallets whose public keys are permanently visible on-chain, making them theoretically drainable by a sufficiently powerful quantum computer. The exposed pool includes Satoshi Nakamoto's untouched ~1 million BTC and any wallet spent from since the 2021 Taproot upgrade, which by design publishes the key protecting remaining funds. A quantum attacker would not need to race a live transaction — they could work through exposed wallets at their own pace using Shor's algorithm, which Google's latest research suggests requires far fewer resources than previously estimated.

The threat is specific: quantum computers cannot break bitcoin mining or the ledger itself, but they can collapse the one-way math protecting wallet ownership. Ethereum has run a formal post-quantum migration program since 2018, with four…