And so can the US government, contrary to what they say. They have been able to crack PGP since 1996 when they dropped the case against Zimmerman. At the time encryption technology was considered a munition under the Munition Control Act of 1954. When they developed the ability to crack PGP the case against Zimmerman was moot. It's never been admitted by the government, but that could be the only reason for dropping a case they had pursued for years.