My point about Manning waiving his rights was primarily in response to this quote from the parent post:
> Government employees who blow the whistle on war crimes, other abuses and government incompetence should be protected under the First Amendment.
Waving the First Amendment around is meaningless when the affected parties have agreed to not reveal classified information and waive their rights as citizens. Arguing that the First Amendment broadly trumps the UCMJ and classification leads to nonsense. As you said, doing so obviously doesn't work. You can make a case that leaks are justified under some circumstances. That case does not involve appealing to the First Amendment.