Eugene and Jeff,
If Eugene is wearing his old Arch-Conservative Hat, let me don my Skeptical Liberal Fedora and rise to the defense of cyber-optimism!
OK, let's talk about crime. It's true, of course, that we still live in meatspace, at least for the foreseeable future. Who argues otherwise? If we're going to live in a real-world society with laws, that by definition means we're going to be yielding at least a little of our freedom, at least some of our ability to do whatever we want at any time. It's a tradeoff, and we benefit from it.
But in a free society, we place strict limits on police power. (All we're arguing about, I think, are how strict the limits must be.) History has shown us that to do otherwise leads at best to an unduly nosy government and at to worst one that veers toward totalitarianism. Even in the United States, government agencies have subjected hundreds of thousands of law-abiding Americans to unjust surveillance, illegal wiretaps, and warrantless searches. Eleanor Roosevelt, Martin Luther King Jr., feminists, gay rights leaders, and Catholic priests were spied on. The FBI used secret files and hidden microphones to blackmail the Kennedy brothers, sway the Supreme Court and, influence presidential elections.
Eugene, you correctly say: "Total security from police searches, either of your home or your encrypted computer, is a serious help to criminals." But I'm not sure I agree that "it's a serious problem not just for the police but for the rest of us."
It strikes me that in the last half-century, our sphere of privacy has been gradually eroding. Technology, in particular mainframes and databases, has been a catalyst. The federal government created the Social Security number in the 1930s for limited purposes, and then repeatedly expanded its use. Massive voracious databases spurred the process along.
Now we're in the age of personal computers, distributed networks, and strong encryption. That's a powerful counterbalance to the database culture.
Now, it's true that if encryption is widespread, it will hinder the FBI's ability to wiretap. It will allow miscreants to encrypt files in a manner impervious to prosecutors' most determined attacks. It will make it more difficult for the National Security Agency to scan international phone calls or e-mail in bulk for code words that hint at illicit activity. It will hinder convictions--but then again, so do Miranda rights.
FBI Director Louis Freeh has said that controls on encryption are a matter of restoring the "balance" that's tilting away from law enforcement. "In a very fundamental way, conventional encryption has the effect of upsetting the delicate legal balance of the Fourth Amendment, since when a judge issues a search warrant it will be of no practical value when this type of encryption is encountered," he told Congress a few years ago.
What Freeh neglects to mention is how the scales are already tipped in favor of the police. Modern communications technologies make it possible for law enforcement agents to collect an unprecedented amount of information on ordinary citizens without their knowledge. Digital technology allows governments to do a much more thorough job of monitoring an ordinary person's actions and opinions than ever before. If the Justice Department ransacks your home, you'll know it. Not so when your communications are digital and are culled from a mail server without your knowledge.
Encryption and other technologies are simply restoring the balance of privacy. As John Gilmore of the Electronic Frontier Foundation puts it, 200 years ago it was possible to go out in a rowboat to the middle of Boston Harbor and have an entirely private conversation free from eavesdropping. Technology fortunately gives us that same ability to do so today--even if our friends, associates, and relatives are on the other side of the globe.
Put another way: In the United States, at least, society should have a strong presumption toward individual rights. The police should not be able to act unless they have constitutional authority and good reason, and their actions should be targeted at one person. I should not be denied privacy because there's a chance my neighbor could--conceivably!--be violating the law.
Back to the balance between freedom and police power. Let's say that come some terrible disasters, such as the ones to which you allude ("crimes that are deadlier than they ever were before"), we as a society choose to weigh the scales more heavily in favor of the police. The National Commission on Terrorism, which is presenting its report to the Senate Intelligence Committee this afternoon, has recommended doing precisely that.
But what about the practical effect of such laws? How can you ban encryption technology that is becoming (with IPv6) hard-wired into the very firmanent of the Internet? How can you restrict anonymity when offshore jurisdictions are so keen on providing it? How can you stop people from talking in private when tools to let them do so are readily available? How can you restrict technology when the history of mankind's progress suggests it's near impossible?
I think the answer is this: We can't. It's not practical, nor is it desirable. Yes, privacy-protecting technology can disrupt society--but, heck, so did the telegraph and the automobile. Police will have to learn to adjust, to try to work around technology with informants or meatspace surveillance.
I admit I may be missing something that is obvious to both of you. Jeff, what do you think?