ムーディーズ、トランプ大統領の命令を受けてビットコインとデジタル資産に対する量子的脅威を警告

Bitcoin Magazine Moody’s Flags Quantum Threat to Bitcoin and Digital Assets After Trump Orders A pair of executive orders signed by President Trump on June 22 has pushed the quantum computing question from the research lab into the boardrooms of crypto exchanges, custodians and stablecoin issuers. In a June 24 sector comment, Moody’s Ratings warned that the credit implications for digital assets are significant, and that the industry now faces pressure to prove it can defend the cryptography at its foundation. The orders make quantum computing and its security a strategic national priority. One directs the development of a quantum computer “powerful enough to initiate the era of quantum-enabled scientific discovery,” with system specifications due within 90 days. A second accelerates the federal migration to post-quantum cryptography, moving preparedness deadlines to 2030-31 from the prior 2035 target. That four-year jump is the detail crypto builders should note. Moody’s frames the risk in stark terms for public blockchains. Bitcoin relies on public-key cryptography to secure ownership, authorize transactions and manage core infrastructure. A sufficiently capable quantum computer could break the elliptic-curve signatures that guard private keys. Unlike a bank wire, an on-chain transaction offers limited ability to reverse a theft or recover funds. As the analysts put it, compromised keys “may lead to immediate and irreversible on-chain outcomes.” The finality that makes Bitcoin trustless also removes the safety net. Moody’s: There is a 2030 deadline for a decentralized network The near-term danger is not a working quantum machine but a strategy called “harvest now, decrypt later.” Adversaries capture encrypted data today and store it for the day a capable machine arrives, an event the industry calls “Q-Day.” For Bitcoin, dormant wallets and reused addresses with exposed public keys form a standing target. Satoshi-era coins, held in early pay-to-public-key outputs, sit among the most exposed. Moody’s expects market participants to face growing demand for “cryptographic agility,” the ability to inventory, update and replace vulnerable algorithms without severe disruption. The firm suggests exchanges, custodians and tokenization platforms will need migration paths toward quantum-resistant standards, plus honest assessments of the exposure in existing wallets, custody arrangements and smart contracts. There is a credit-rating logic underneath the warning. Institutions that present credible quantum transition plans, Moody’s argues, stand better positioned to win adoption from regulated financial players and to satisfy rising supervisory expectations on cyber resilience. For a sector courting Wall Street and pension money, quantum readiness becomes a gatekeeping requirement rather than a distant science project. For Bitcoin, the technical fix exists in the form of proposed quantum-resistant signature schemes, but adoption demands consensus, soft forks