In what sense was Martin "doing the right thing" by hoarding documents seemingly for its own sake/to satisfy some tick? I don't think it's fair to the others you listed to lump Martin in with them.
Assange isn’t even subject to US law and doesn’t/didn’t have a clearance. They’re going after him on whatever grounds they can scare up simply for publishing.
It’s part of a wider plan, to shore up the fact that they are vulnerable, which Snowden most effectively demonstrated.