# Harvest Now Decrypt Later The intelligence strategy of intercepting and storing encrypted communications now, with the intent of decrypting them once a cryptographically relevant quantum computer exists. This is why the quantum computing threat is present-tense, not future-tense: data intercepted today may be readable in 10–15 years. The logic is straightforward: encrypted traffic captured by signals intelligence agencies (NSA, GCHQ, Chinese MSS) is currently unreadable. But if that encrypted traffic is stored — and storage is cheap — a future quantum computer running [[Shor's Algorithm]] could decrypt it all retroactively. Classified communications, diplomatic cables, corporate trade secrets, personal medical records — anything encrypted with RSA or ECC today is potentially vulnerable to future decryption. This strategy explains why the U.S. government is pushing for immediate adoption of [[Post-Quantum Cryptography]] even though useful quantum computers are years away. The window of vulnerability is not "when quantum computers arrive" but "everything between now and when PQC is fully deployed." Every day of delay adds to the stockpile of intercepted data that adversaries could eventually read. The [[FISA Section 702]] surveillance infrastructure and the broader signals intelligence apparatus documented in the [[Surveillance Lexicon]] are the collection systems feeding the "harvest" side of this equation. ## See Also - [[Post-Quantum Cryptography]] — the defense - [[Shor's Algorithm]] — the quantum attack - [[Quantum Computing]] — the enabling technology - [[FISA Section 702]] — the collection authority - [[Technology Lexicon]] — the full vocabulary (quantum computing section) - [[Surveillance Lexicon]] — the monitoring context