Your question is a bit mute, because someone's hero is always someone's enemy at the same time, and it can't be any other way.
And it does not matter if he's narcissistic or not, the info is still useful.
Personally I do not care about America's reputation much, but I was not particularly surprised or excited by these "revelations" either, so I'm neutral about him.
Is he an American citizen? I guess in this case it can be considered a treason, and he can be prosecuted legally for revealing secret information (if there were real secrets). If he's not, American secrets are fair game.