You haven't paid much attention, I think. The cables have revealed plenty of illegal activity. Much of it was illegal foreign affairs that the U.S. was simply aware of. It's had global impact.
Sorry, that was poor word choice on my part where the context wasn't clear.
None of the information in the Wikileaks cables contained illegal activity
that would be legal justification for a whistleblower defence.
A part of this is due to the only illegal activity being revealed being overseas, and the cables in those cases amount to no more than two people swapping a text or email over rumours of a third person's drug taking. As a rule, if a leak can't result in a direct legal remedy then a whistleblower defence is near impossible. For some cables you can almost make a public interest defence, but even there it would be hard to press in US courts given the nature of the information exposed and method of it's exposure.
I just want to lay out very clearly my full view on this part of the case.
Given Manning's own statements, the evidence of the leaks themselves and everything else about this case, it does appear he has broken at least some of the laws he has been charged with.
Given his method of leaking he almost certainly doesn't qualify for whistleblower protections. For one thing he did not take the channels approved for such whistleblowers (contrast with
Daniel Davis).
Some of the leaks certainly were in the public interest, broadly defined, and did a net good. However, due to the method and broad nature of the leaks it's hard to say that Manning served the public interest effectively. If I fire a hundred bullets indiscriminately downrange and two hit the target I can't point at those two and say I'm an effective marksman.
Similarly, given the scale of the leaks and the fact Manning didn't tailor them to a specific public interest, Manning is vulnerable to charges of releasing information that may assist the enemy. His willingness to release information indiscriminately means such a charge can be brought even if no such damaging information existed. I personally think he
should be found not guilty of that charge, but this is more for mitigating circumstances than for a plain law reading of his actions.
Going back to the public interest defence, I'm afraid that even if such a defence could be made for specific leaks (as for, say, the Collateral Murder video or elements of the Afghan/Iraq war logs) it is unlikely it would be sufficient for legal defence. Ellsberg understood this back in the 70's. When the Supreme Court ruled that the Pentagon Papers were illegally released Ellsberg turned himself in and stated he was willing to face, "all the consequences of this decision." He was later released due to illegal and other improper behaviour by the prosecution, not due to any legal defence of the leak.
This is pretty important to recognise. Even when leaks are in the public interest
they may not be legal. Acts of justified public disobedience do still come with legal penalties and even jail time. Committing a crime lots of people like doesn't mean the crime itself is (or should be) ignored by the state.
Further to all this, exactly what remedies and treatment Manning deserves really depends on his trial. If he comes out of it with an excessive punishment then Presidential clemency may be appropriate (which is what this whole debate was about).