This was an interesting argument, so I did some quick research. Apparently, six (6) Espionage Act cases have been filed under Obama. I found and read the indictments for each (they're easy to find, since FAS tracks them). They were:
* Thomas Drake, an NSA employee who favored "ThinThread" instead of the later-adopted "Trailblazer" internet surveillance scheme, who then created a Hushmail account and fed classified documents to a reporter from it.
* Shamai Leibowitz, an FBI contractor/interpreter, who fed the contents of an cable intercepted from the Israeli embassy to a blogger because he felt it implicated Israel in an attack on Iran.
* Stephen Jin-Woo Kim, a career civil servant at State who worked on counterproliferation and North Korea and fed classified documents about North Korea to Fox News, and then lied to the FBI about having any contact with journalists.
* Bradley Manning
* Jeffrey Sterling, who was fired from the CIA, lodged a series of employment law disputes with the CIA, attempted to write a memoir about his time at CIA, and then fed classified details about Iranian counterproliferation to a reporter which put a human intelligence resource at risk.
* John Kiriakou, a CIA counterterrorism official who worked in Pakistan, who outed two covert operatives to a reporter (they had allegedly been involved in the Bush-era interrogation program).
Of this list, Kiriakou and Drake are sympathetic to me, but every single case here seems like a valid prosecution; when you take a role that requires you to handle the most sensitive data the government handles, you cannot share it with the press expecting not to end up arguing your side of the story in a court of law. You certainly can't out covert operatives, or feed foreign intercepts you translate to bloggers!