I tend to look at it from this perspective: What if a government agent turned rogue and released similar documents highlighting similar activities? In this case, however, it's North Korea, China, or Russia that had a leaker. The issue isn't whether it's legal or not. Corrupt regimes and governments often employ various complex laws to keep people silenced, and in many cases if it wasn't our own government we would applaud people for taking the risks to expose their corrupt government. Unfortunately, when it comes to us, we just accept certain laws at face value and in some cases support them fully, even with the reality being that those laws help support corrupt government practices.