National Security encompasses everything from the economy to our infrastructure. Having such a deep infiltration on major regional players like Brazil and Germany helped us to better allocate our resources against potential issues. We would have advanced warning against German impatience with Greek debt, we would have advanced warning on regional conflicts between Brazil and Venezuela. Spain is a major source of European debt, and knowing what discussions were going on among their government officials was a massive advantage.
With those kinds of early warnings, we could have known when it was safe to put money into helping solve the debt crisis by working with those nations while also knowing when the entire system was about to collapse and to reinforce our own economy. With our infiltration of Mexico, we would have known when a possible crackdown on drug cartels would increase crime rates along our border, or if there were any operations we weren't aware of that might have impacted our intelligence community's analysis of the situation (a crackdown looking like a turf war, or even knowledge of border operations they weren't willing to share). Mexico has been unwilling to work with us lately, and being able to see that deep into the situation was allowing us to worry about other things.
Are you really gonna say that those aren't in our national interest? All we did was tap some phones. Who did THAT hurt? Are you really gonna believe a butthurt German government who has egg on its face over our own security officials? I don't agree with what they're doing domestically, but what they were doing internationally wasn't even REMOTELY out of the ordinary. Spies have literally been doing these sorts of things for centuries, from intercepting telegraph wires to installing bugs in consulate buildings to stealing scientific research to help develop their nuclear capability.
We knew what talking points to go over with Ban Ki Moon, we knew about France and Germany's economic conversations, and we also knew about their willingness to get involved in a operation over Syrian chemical weapons (which France ended up being a huge help to us over, so that was nice to know about before we floated it internationally). The Brazilian space program, as well as access to THIRTY FIVE other leaders. We've had decades of globalization from Republican warmongering to Democrat aid-offering. We're so tied down to the rest of the world that we HAVE to know when shit is about to hit the fan, otherwise American citizens suffer domestically because of foreign affairs. That's the entire point of National Security. If it weren't encompassing the entire breadth of our national interests, it'd be called "Anti-Terrorism Agency" instead of "National Security" agency.
He's exiled? No, he's self-exiled. He can't come back because he refused to let the justice system do what it was designed to do. Whistleblowers have come and gone. Bradley Manning got off fairly easily, and will always be remembered as a hero. Snowden shouldn't get that same right. He isn't even in Manning's league.
Under Article III, Section 3, of the Constitution, any person who levies war against the United States or adheres to its enemies by giving them Aid and Comfort has committed treason within the meaning of the Constitution. The term aid and comfort refers to any act that manifests a betrayal of allegiance to the United States, such as furnishing enemies with arms, troops, transportation, shelter, or classified information. If a subversive act has any tendency to weaken the power of the United States to attack or resist its enemies, aid and comfort has been given.
Did he manifest a betrayal of allegiance? Yes.
Did he provide enemies (and everyone else in the fucking world) with classified information? Yes.
Did his act weaken our power to resist or attack our enemies? Considering we were listening in to international leaders' phone calls, texts, and emails, yes, he did.
Therefor, treason by the technical definition according to the U.S. Constitution.