secure, since my public key would be available to anyone who wanted it. But it would give my email an unforgeable "digital signature." (Endnote #34)

This system works because my private key never leaves my grasp. No more nightmares about the code book falling into the hands of the enemy.

But here, the government gets into the act. The intelligence and law enforcement branches of the United States government -- the National Security Agency (NSA), the Central Intelligence Agency (CIA), the Federal Bureau of Investigation (FBI), and the Justice and Treasury departments -- don't want U.S. citizens using encryption systems they can't break. They claim it's a national security risk and that unbreakable encryption would be a boon to child pornographers. The government has proposed its own encryption scheme -- called Clipper -- which is being developed specifically so that government agencies will keep copies of everyone's keys.

You could legitimately ask why anyone cares that much about the security of their private communications. After all, what email do you send that it would be that big a deal for someone else to see? And anyway, why would anyone want to read your mail? But privacy-advocacy groups point out that the government doesn't have a great record of using its surveillance powers wisely. Think back to the McCarthy communist-hunts of the 1950s and the disruption of political groups in the 1960s. More recently, we had the "war on drugs" of the 1980s, which gave state and federal governments extremely broad rights of property seizure.

Historically, these weapons have been used against poor people, minorities, and social and political activists. Perhaps you're sure you'll never fall into any of these groups. For myself -- although I'm generally in favor of having a government -- I'm not sure I want all of my communications to be an open book to the FBI. In addition, the existence of a