The idea that Snowden is not a "whistleblower" because he didn't go through internal government channels to make his claims is absurd on two fronts. First, at the time Snowden gave his material to the Guardian and Washington Post, he was a government contractor, and contractors were exempt from most whistleblower protections given to national security employees. (Politifact called Hillary Clinton's statement that he had access to whistleblower protections "mostly false.")
But this argument is a red herring anyway. Snowden was not blowing the whistle on some rogue NSA agent or a program that only a handful of people knew about. These mass surveillance programs (later ruled illegal) were approved at the highest levels of the executive branch and by the Fisa court. Snowden would have essentially been telling his superiors, who already knew about them and were tasked with carrying them out, that they themselves were breaking the law.
Snowden did not "flee" to Russia and has regularly criticized Russia's human rights record
There is a persistent yet false accusation that since Snowden is in exile in Russia, he "fled" there and has cooperated with the Russian government (in the words of the Post's editorial, "Mr Snowden hurt his own credibility as an avatar of freedom by accepting asylum from Russia's Vladimir Putin").
This is false. The only reason he is in Russia is because the US government canceled his passport as he was transiting through the Russian airport to Latin America. He was marooned there against his will. Everyone, including Snowden himself, wishes he wasn't in Russia, but the alternative is being thrown in a maximum security prison in the United States. At least right now he is free to participate in the international debate virtually.
Snowden has harshly criticized Russia's human rights and civil liberties record so many times at this point that it is hard to count (including, in 2014, in an op-ed for the Guardian). Snowden's condemnation has been so strong that the former US ambassador to Russia (and Snowden critic) Michael McFaul recently tweeted: "@Snowden makes a stronger statement about human rights regression in Russia than anything I ever said as [Ambassador]. Wow."
He cannot make his case to a jury in what the Post called the "best tradition of civil disobedience"
In a perfect world, Snowden could come home and tell his story to a jury, as many of his critics say he should. However, this belies a fundamental misunderstanding of the law Snowden is charged under. The Espionage Act -- a first world war-era statute meant for spies, not whistleblowers who give information to the press -- does not allow for a "public interest" defense. Snowden would literally not be allowed to tell the jury his motive for leaking the information, describe the benefits of the disclosures, or discuss their lack of harm to national security.
The most famous whistleblower in American history, Daniel Ellsberg, has made this point repeatedly and is on the record as saying that Snowden was right to leave the country so he could continue to participate in the public debate around his disclosures.
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