Venture capitalist Nic Carter has accused the Bitcoin development community of "sleepwalking" toward a catastrophic security failure, warning that the network is unprepared for the looming threat of quantum computing. The Castle Island Ventures partner’s comments ignited a fierce public spat with Blockstream CEO Adam Back, exposing a widening rift between institutional allocators and protocol maintainers as Bitcoin hovers precariously around $88,000.
The 1.7 Million BTC Vulnerability
At the core of Carter’s warning is a specific technical vector: the estimated 1.7 million BTC held in legacy Pay-to-Public-Key (P2PK) addresses. Unlike modern addresses which hash public keys, these early outputs, including the vast majority of Satoshi Nakamoto’s estimated holdings, expose the raw public key directly on the blockchain.
Carter argues this exposure makes them "low-hanging fruit" for a quantum attacker running Shor’s algorithm, which could theoretically derive private keys from exposed public keys long before breaking the rest of the network’s encryption. While the timeline for a "cryptographically relevant" quantum computer remains debated, the sheer volume of at-risk capital—roughly $150 billion at current prices—creates a massive "bug bounty" for nation-state adversaries.
"The problem is that Bitcoin culture treats ‘not imminent’ as ‘not urgent,’" Carter noted, arguing that the logistical nightmare of migrating these coins requires years of preparation that isn’t happening.
"Uninformed Noise": The Developer Pushback
The critique drew an immediate, sharp rebuke from Adam Back, the Blockstream CEO and Hashcash inventor cited in the Bitcoin whitepaper. Back dismissed Carter’s alarmism as counterproductive, insisting that developers are already researching quantum-resistant signature schemes (like Lamport signatures) behind the scenes.
"You make uninformed noise and try to move the market or something. You’re not helping," Back
