Diffusion of responsibility is definitely a defense in these cases, but the system should recognize this shortcoming and assign accountability (at least in an ideal world).
Although I'm willing to bet that the true actors here weren't necessarily presidents (even though they would ultimately be accountable like you say). Would be interesting to see who demanded what and when.
It's not to lionize Assange, but these are almost crimes against humanity, they stole peoples tax dollars and then built a surveillance state used against the citizens. When that was revealed they then used the same tools to destroy a single human being for the purposes of creating a decade long chilling effect for anyone who might consider doing the same.
There shouldn't be any diffuse responsibility for participating in this farce at any level. When the information was released the public never clamored for it to be investigated and for people to be hunted down and jailed for releasing it. It was entirely a captured administrative state claiming for itself rights it demonstrably never had, such as claiming a foreign national committed treason, or that he could be viewed as an "enemy combatant."
To have gone along with this willingly deserves the same scrutiny we gave German officers at the end of WWII.
> There shouldn't be any diffuse responsibility for participating in this farce at any level.
I would argue there should, no exception. Not even WWII. While keeping in mind that the responsibility was so gigantic to begin with, that even diffusing it might end up putting most participants in jail, some of them for a long time.
Although I'm willing to bet that the true actors here weren't necessarily presidents (even though they would ultimately be accountable like you say). Would be interesting to see who demanded what and when.