"Except in times of war any individual or employee or government who withholds secrets from friends, employees or citizens has effectively declared war on them. Despite all the spurious reasons given by individuals, employers and governments for having secrets it reduces to the zero-sum winning and losing game scenario wherein the individual, employer or government are afraid to lose or hope to make someone else lose." Arnold Arnold - Winners And Other Losers In War And Peace.

Serious question - has he actually been convicted of anything yet?

However in general it seems like a case where "the ends justify the means" but the means are still technically illegal, is a perfect situation where a pardon can be used to right a wrong. I mean the phrase "his actions were pardonable" fits perfectly doesn't it? Sadly we pretty much squandered the opportunity for change for good after the many 2010s leaks. The fix is still in and endemic corruption, illegal surveillance, tax evasion, and many other things are still going on at a break-neck pace last I checked. And that's just the stuff we know about...

Meanwhile Trump pardons anyone who did him a favor no matter how provably guilty they are of acting purely to preserve a private interest - Trump. I very seriously doubt he will actually pardon Snowden. But if eventually someone else does you can bet he'll try to take credit for it. And if he is never pardoned Trump will also take credit for that. He always likes to cheat and play both sides.

Yes because whistle blowing and the uncovering of war crimes is heroic, not treasonous.

Trump will never grant him one though and if he does, Snowden would be a fool to accept.