I don't know much about the story, but a couple thoughts:
1) High-level officials disclose classified information with no or little consequence. For example, someone in the Bush administration outed CIA agent Valarie Plame for political reasons, and General Patraeus disclosed classified information and got a slap on the wrist. And they leak it to the media regularly.
2) It could be that they didn't care about the leak but wanted to prosecute him and found a reason, found in his years of service and in his actions something they could charge him with.
To slightly adjust a British military saying, you need to remember your irregular verb "to leak":
The soldier commits a Federal crime.
The junior officer displays a marked lack of integrity.
The senior officer delivers an off the record briefing to the favoured reporter.
You're right, there are definitely major double standards with leaking of sensitive data. It's absurd that Petraeus wasn't charged with a felony (my understanding is many people in the DoJ wanted him to receive much harsher charges). Clapper should be charged with perjury as well.
The Plame case is a bit different, because the person who originally leaked the name was not actually aware she was covert.
1) High-level officials disclose classified information with no or little consequence. For example, someone in the Bush administration outed CIA agent Valarie Plame for political reasons, and General Patraeus disclosed classified information and got a slap on the wrist. And they leak it to the media regularly.
2) It could be that they didn't care about the leak but wanted to prosecute him and found a reason, found in his years of service and in his actions something they could charge him with.
My point is, I wouldn't take it at face value.