I suspect that if someone did source research by breaking the security of your computer, you would want them prosecuted, too. Journalists can't be persecuted for what they write, but they're not above the law.
Sure, in the same sense that the same description could apply to torturing someone with relevant knowledge.
Freedom of the press is the right to publish, not an exemption from all criminal law so long as the object of the crime is acquisition of material for publication.
This actually seems like great news for journalists. The fact that this is the only charge implies that prosecutors have decided that wikileaks’ core activity of publishing classified information obtained by others was actually legal.
The fact that assisting someone to break into a DoD computer turns out to be illegal probably shouldn’t surprise anyone. If someone asked for your help breaking into a DoD computer would you say “oh sure, that sounds like a perfectly legal thing that can’t possibly get me into trouble”?
I wouldn't underestimate the US. They could be laying this nice, comfy-looking trap to ease the extradition process from UK. Then once on US soil, the real charges are unveiled.