A new method of communicating is creating intriguing services that beat old ways of sending information. But law enforcement makes a somber claim: These new networks will become a boon to criminals and terrorists unless the government can easily listen in.
This was the story line in the mid-1990s when the Clinton administration sought to have electronic communications encrypted only by a National Security Agency-developed "Clipper Chip," for which the feds would have a key.
The Clipper Chip eventually went the way of clipper ships after industry balked and researchers showed its cryptographic approach was flawed anyway. But while the Clipper Chip died, the dilemma it illuminated remains.
With each new advance in communications, the government wants the same level of snooping power that authorities have exercised over phone conversations for a century. Technologists recoil, accusing the government of micromanaging - and potentially limiting - innovation.
Today, this tug of war is playing out over the Federal Communications Commission's demands that a phone-wiretapping law be extended to voice-over-Internet services and broadband networks.
Opponents are trying to block the ruling on various grounds: that it goes beyond the original scope of the law, that it will force network owners to make complicated changes at their own expense, or that it will have questionable value in improving security.
No matter who wins the battle over this law - the Communications Assistance for Law Enforcement Act, known as CALEA - this probably won't be the last time authorities raise hackles by seeking a bird's eye view over the freewheeling information flow created by new technology.
Authorities are justified in trying to reduce the ways that technology helps dangerous people operate in the shadows, said Daniel Solove, author of "The Digital Person." But a parallel concern is that technology can end up increasing the government's surveillance power rather than just maintaining it.
"We have to ask ourselves anew the larger question: What surveillance power should the government have?" said Solove, an assistant professor at George Washington University Law School. "And to what extent should the government be allowed to manage the development of technology to embody its surveillance capability?"
Wiretapping - so named because eavesdropping police placed metal clips on the analog wires that carried conversations - has a complex legal history.
A 1928 case, Olmstead v. United States, legitimized the practice, when the Supreme Court ruled it was acceptable for police to monitor the private calls of a suspected bootlegger.
Behind that 5-4 ruling, however, a seminal debate was raging. The dissenting opinion by Justice Louis Brandeis argued, among other things, that the government had no right to open someone's mail, so why should a phone - or other technologies that might emerge - carry different expectations about privacy?
In 1967, as the dawn of the digital age was fulfilling Brandeis' fears that other forms of technological eavesdropping would become possible, the Supreme Court reversed Olmstead. After that, authorities had to get a search warrant before setting wiretaps, even on public payphones.
That apparently hasn't been much of a hindrance.
State and federal authorities have had 30,975 wiretap requests authorized since 1968, with only 30 rejections, according to the Electronic Privacy Information Center. Some 1,710 wiretaps were authorized last year, the most ever, with zero denied.
Since 1980, authorities also have been able to set secret wiretaps with the approval of the Foreign Intelligence Surveillance Court, which privacy watchdogs say requires a lower standard of evidence than the general warrant process. For the first two decades FISA orders numbered less than 1,000 annually; 2003 and 2004 each saw more than 1,700. Only four FISA applications have been rejected, all in 2003.