Frankly I think he should pardon Snowden and Assange (if he's gonna give people the bird why not extend it to the establishment) and Joe Exotic (because the lulz of doing that would be on brand for him) while he's at it. Unlike Levandowsky, Snowden and (to a lesser extent) Assange are deserving of pardons in much of the public's eyes.
It licences the principle that intelligence can be leaked without legal consequence "by the conscience" of the leaker.
Is that really how intelligence should be conducted? Most people are idiots; and do not know the ramifications of what they do.
It is perfectly reasonable for something to be both moral and illegal, and remain punishable. Ie., it is Good that these leaks occured, but nevertheless, we require the leakers to pay some cost for it.
If that cost is "in practice" merely exile from the country, that seems a reasonable compromise.
Edit: I do think I understand your overall point though. Actually leaking information should be a very serious decision, and should not be taken lightly.
That is to say, if e.g. Snowden's actions were civil disobedience, it's not incoherent to say both that:
1. He was right to leak the info, and
2. He need not be pardoned in the name of justice.
And I do believe this is inconsistent if you believe that justice has anything to do with right and wrong actions.
Your argument is:
1. There are right and wrong actions. 2. Justice does not decide or even attempt at determining right and wrong. 3. Therefore doing something right or wrong has no bearing on the outcome of our justice system.
As an individual, what your are saying is important and I agree. We have to call upon ourselves to do the right thing in spite of the consequences. But often times civil disobedience seeks to change the injustice of the current system and if that system never changes or adapts as a result then the outcome will always be the same. This may have happened in the case with Snowden (though we can still correct it) but it has not been the same throughout history. I’m very glad that we did not simply exile all our civil rights leaders with no thought given toward bringing a greater sense of fairness to our judicial systems.
I take extreme exception to the idea that somebody should be punished for an act generally considered moral by the public for the purpose of dissuading others.
If some idiot takes it upon themselves, based on a pardon of Snowden, to reveal something not in the public interest and harmful to the state, let them be punished as a warning to others. Leaks of state secrets have been a reality since the beginning of civilisation, one more isn't going to destroy us.
Assange is much more controversial, especially now that he won't be extradited and prosecuted, since his crimes are much more political and he wasn't tactful like Snowden, he published everything he got. There's definitely less public support for his pardon but if the goal is to give the middle finger to the establishment this is the better one because it is controversial.