But now that the world's most famous leaker has apparently left Hong Kong for Moscow (and beyond), that support has begun to erode. Some of the best-known whistleblowers of the past decade are now concerned that Snowden's flight to America's geopolitical rivals will make it easier to brand tomorrow's whistleblowers as enemies of the state.

"As for unclassified whistle blowing it is doubtful that government employees will risk going outside their chains of command in the future," Franz Gayl, a fierce internal critic of the U.S. Marine Corps, tells Foreign Policy in an e-mail. "Folks who would risk their careers by placing the good of the country ahead of the good of parochial agency interests may be history."

That isn't just a problem for guys like Gayl. It's an issue for all of us. Creaky bureaucracies tend to maintain their dysfunctional ways until they're shocked into action. A whistleblower can deliver the most effective bolt. Just look at the NSA, which says it's introducing new privacy precautions in the wake of Snowden's leaks.

But government workers who expose problems within the system are often made miserable for doing so. Take Gayl, a civilian scientist for the Marines. In 2007, after a tour in Iraq, he revealed to the press and to Congress that the Pentagon was dragging its feet on urgent requests for bomb-resistant vehicles and other gear from the war zone. His revelations eventually pressured the secretary of defense to pour billions into the armored trucks, saving countless lives. But for the Marine Corps bureaucracy, the sin of going outside the system was unpardonable. The Marines accused him of stealing intellectual property and mishandling sensitive information. They gave him bottom-of-the-barrel performance reviews and do-nothing jobs. Finally, they stripped Gayl of his security clearance, which effectively prevented him from working at all.

Eventually, that clearance was restored. These days, when Gayl speaks to reporters, he's careful to note that it's as a private citizen, not as an employee of any government agency or military branch. But at least he has a job. Gayl wonders whether other internal critics of the U.S. government will be so lucky. "Interestingly, some leaders in government have publicly begun to morph the description of a legitimate WBer [whistleblowers] into a person who only raises concerns through the chain of command - and stays within it. By changing the government's definition of what a WBer is it regains control over the problem of embarrassing disclosures, especially unclassified ones," he writes. "Agencies have many tools to designate and confirm threats, including - but not limited to - dreaded fitness for duty psychiatric exams. In the years and decades to come, this introduction of fear will likely transform the objective, patriotic, and constitution-abiding civil servant of our fine tradition into a timid - though still ambitious and opportunistic - party apparatchik. Such sycophant survivors were common in 20th Century totalitarian regimes who we remember as our sworn enemies. "

Given the pressures that an unclassified leaker like Gayl faced, it makes some sense for Snowden -- who exposed top-secret programs -- to leave the country. He's the seventh man accused of being an enemy of the state by the Obama administration, and the other six haven't exactly fared well; three are in jail and two more are in court. "What is unfolding is not surprising, given that our laws encourage leaks since there are very weak protections for intelligence whistleblowers and none for intelligence contractors who make legal disclosures," says Danielle Brian, who has worked with whistleblowers for decades as executive director of the watchdog group the Project on Government Oversight. "Although I will say that I think he is getting the worst possible advice. He is taking a path that makes it easier for the public to believe the charges against him and the claims by those who seek to demonize national security whistleblowers."

"By fleeing to foreign countries of questionable taste, [Snowden] has taken his acts beyond the normal American view of a whistleblower," adds veteran investigator Glenn Walp, who exposed huge security holes at Los Alamos Nuclear Laboratory. "Ultimately he will not be remembered or identified as a whistleblower, but rather, in most circles, as a traitor - that's the difference."

Other whistleblowers have latched onto Snowden's recent admission that he took his job with Booz Allen Hamilton for the sole purpose of gathering evidence on the NSA's cyberspying networks. "That's not how a whistleblower behaves," said Martin Edwin Andersen, a former whistleblower who exposed misconduct within the Justice Department. "He had a number of legal recourses he could have pursued; for example, he could have gone to Congress, where many members -- Democrat and Republican, liberal and conservative -- regularly and vocally challenge the system. Instead, he knowingly went back on his word and broke the law." 

The whistleblower community isn't monolithic, however. Some of the people who have most famously revealed the NSA's secrets are standing by Snowden. And they believe that the fuss around Snowden's itinerary is far, far less important than the substance of his disclosures. "It's not for me to criticize Snowden's choice of countries to flee to. He's clearly trying to stay out of the clutches of the U.S. government, which would surely treat him badly if they got a hold of him," says Mark Klein, the AT&T employee who in 2006 made public the NSA's wholesale monitoring of the telecom's voice and data traffic. "My view is: I hope he stays free and healthy as long as possible."