For example, look at crypto algorithms like DES that, ten years ago, people thought would take thousands of years to crack given Moore's law growing computation

For example, look at crypto algorithms like DES that, ten years ago, people thought would take thousands of years to crack given Moore's law growing computational resources. Wide freakin' open now, thanks to improved cracking algorithms. Any message sent via classical channels can be copied without your knowledge, so any message you sent via DES ten years ago could be decrypted and in anyone's hands without your knowledge. I think your history is incorrect. See this: http://en.wikipedia.org/wiki/Key_size#Symmetric_algorithm_key_lengths http://en.wikipedia.org/wiki/Key_size#Symmetric_algorithm_ke... People were unhappy with 56 bits right off the bat in 1977. There were export-control restrictions. Some people believed NSA had on purpose degraded the key-size. People were thinking of getting around DES in the early 90s itself. First triple DES (for backwards compatibility) and now AES.