Can Quantum Computing Actually Break Bitcoin?

KEY TAKEAWAYS Google Quantum AI published a March 2026 whitepaper estimating that breaking Bitcoin 's ECDSA 256 encryption requires 20 times fewer qubits than previously projected in 2019. Roughly 6.9 million BTC, approximately 32% of the total supply, sit in wallets with public keys already exposed on the chain. Researcher Giancarlo Lelli cracked a 15-bit elliptic curve key on 24 April 2026,…