We recently learned that even the director of the CIA, David Petraeus, can’t seem to secure his private e-mail conversations properly, and over the past month tech commentators have responded to that discovery with a familiar litany of depressing advice: Privacy doesn’t exist online, e-mail is as public as a postcard, and don’t say anything on the Internet you wouldn’t want to read in the newspaper. Civil libertarians, meanwhile, have urged the need for legal reforms—such as a proposal just approved by the Senate Judiciary Committee to require police to get a warrant before obtaining e-mails or personal files stored in the cloud, which Congress is likely to consider next year.

Yet politics, as we all know, moves much more slowly than technology. The courts aren’t much better: It was only in 2010 that a federal appeals court first ruled that the Fourth Amendment does, in fact, apply to e-mail, while the status of other types of digital records remains murky. Yet there is one company in an ideal position to dramatically increase e-mail privacy for hundreds of millions of users overnight, offering protection from malicious hackers as well as nosy governments—the same company, ironically, from which the FBI obtained Petraeus’ e-mail: Google.

Back in the 1990s, so-called Cypherpunks waged a successful battle to loosen regulations on strong encryption software, dreaming of the day when the everyday communications of ordinary Internet users were protected by unbreakable digital locks. That vision has been only partly realized: We now have a vibrant and growing digital economy made possible by the routine encryption of commercial traffic, but routine encryption of e-mail contents is still largely seen as the province of geeks and paranoids, too arcane for the average user.

One reason is that encryption, like the telephone or e-mail itself, is what economists call a network good: Its value to the individual user depends crucially on how many other people are using it. An e-mail account isn’t much use if you’re the only person you know who’s got one, and spending time figuring out how to use a suite of encryption tools only make sense if the people you want to write are using compatible tools. Moreover, encrypted communication requires a trustworthy repository of public keys, tied to individuals’ identities or e-mail addresses, so that only the true intended recipient of an encrypted message can unlock it with their private key.

425 million and counting

Google is in an ideal position to overcome these difficulties, and finally make strong e-mail encryption a mass phenomenon. Their Gmail service—the one David Petraeus was using to exchange steamy messages with his biographer and lover, Paula Broadwell—has some 425 million active users by last count. Many of those users access the service through a Web interface, which Google can change and update for all users simultaneously. That means we could all wake up tomorrow to find a handy new “Encrypt Message” button included in the familiar Gmail interface we’re already using. Meanwhile, Google (along with Facebook) has rapidly become a kind of universal Internet identity provider, with the Google Account used as a key not only to access Google’s own myriad offerings, but many other independent online services as well.

The average Internet user, with little direct experience of truly secure communications, may not see what the fuss is about.

Because truly strong encryption is “end to end”—meaning the end-users generate, store, and have sole access to their own private encryption keys—a robust content encryption system may require users to have appropriate client software installed on their own machines. Here, too, Google is well positioned to provide a solution: They already make a widely-used browser, Chrome, and a popular operating system for mobile devices, Android, which could be updated with the necessary functionality built-in, eliminating the need for a separate browser plug-in.

Though it often takes flak from privacy advocates, Google has a history of taking steps to advance user privacy: In 2010, the company activated HTTPS as the default protocol for Gmail users, ensuring that traffic between Google’s servers and the end-user would be automatically encrypted. (Facebook, another popular privacy whipping boy, followed suit only this year.) It also offers two-factor authentication, which helps guard against hackers by requiring a special code, sent by SMS to the user’s cell phone, whenever someone logs in from an unrecognized device. Yet because Google itself ultimately holds the keys to each account, these safeguards aren’t much use if the company’s own systems are compromised—as has already occurred in a series of recent attacks targeting Chinese dissidents—or when a government (whether that of the United States or some nastier regime) comes knocking with a subpoena.

So why hasn't it already rolled out strong encryption for end users? Well, because Google isn’t a charity: It's a business that is able to provide an incredible array of free services because they can profit from serving up highly targeted ads, enabled by sophisticated analysis of all the data their users generate. As “grandfather of the Internet” Vint Cerf, now Google’s Chief Internet Evangelist, explained to privacy activist Chris Soghoian at a panel last year, “we couldn't run our system if everything in it were encrypted because then we wouldn't know which ads to show you.” In other words, if your e-mails are secured with a lock that Google itself can’t open, then it can’t scan your e-mails for keywords in order to show you ads for Parisian restaurants when you’re writing your friends about an upcoming trip to France.

Fair enough: Nobody expects Google to blow up the business model that makes possible all the cool free stuff it offers. But precisely because it has expanded into such a wide range of integrated services, Google is hardly dependent on keyword analysis of e-mail to target ads: It can still use all the information gleaned from users’ search histories, social or location profiles, and favorite YouTube videos. Moreover, even the most privacy-conscious Gmail users are hardly likely to encrypt “everything”: The vast majority of nonsensitive messages would probably still be sent in the clear. Meanwhile, Google would garner enormous goodwill from privacy advocates, reams of free press coverage, and an attractive new selling point, not only for Gmail but for Chrome and Android as well. Encryption would likely be a particularly appealing feature for Google’s paying enterprise customers, whose messages may contain information that is not only private but highly valuable. At the very least, it’s worth running the numbers again to see whether offering strong encryption might now be a net boon to the company’s bottom line.

Backdoors to come?

There is, finally, a powerful political reason to introduce strong end-to-end encryption now, beyond the obvious benefits for individual users. The FBI, which fears that its digital wiretaps will “go dark” as encrypted communications become more popular, has been quietly but vigorously promoting an update to the Communications Assistance for Law Enforcement Act to cover providers of online communication services like Google and Skype. Just as phone companies have to build wiretap capability into their networks, they want Skype and Google to build in centralized backdoors for law enforcement: Strong end-to-end encryption would be out, as companies would be required to hold copies of the keys to all “secure” communications for police convenience. This myopic move would drastically reduce the security of everyone’s communications in the name of making it a bit easier to spy on a tiny handful of criminals. It’s also unlikely to do much good: If criminals know that Google can’t offer truly secure communications, there’s no way to stop them from simply employing their own unbreakable encryption.

The government could still obtain the encrypted e-mails from Google, of course, but would need to get the key from the user in order to actually read them—but that's no greater burden than police have historically faced with an individual's private papers.

While civil libertarians and privacy advocates are sure to resist any such proposal, the average Internet user, with little direct experience of truly secure communications, may not see what the fuss is about. It’s an iron law of politics: Because people are loss-averse, taking away something people already have and value can be all but impossible—while preventing them from getting it in the first place is far easier. By rolling out e-mail encryption now, Google can ensure that ordinary users see myopic efforts to regulate secure communications infrastructure as something that affects all of our privacy and security—not just that of faceless crooks or terrorists.

Google has already transformed our daily lives in an astonishing variety of ways—from how we find information online to how we find a restaurant in a new city—but it has also been cast, from time to time, as a privacy villain in the process. Now it has an opportunity to transform how the public views the privacy of e-mail communications—while burnishing its own reputation in the process.