The contents of that opinion are still classified, and in fact, just last week, the Daily Beast called FISA court opinions some “of the most highly classified documents inside the U.S. government.” Does David Gregory think he should be charged with a crime for talking to sources, asking questions about classified information, and then reporting what he learned?

Gregory defended his question after the fact by saying Congress is having this “debate” about whether Greenwald should be prosecuted. In reality, there is no debate. One Congressman, Peter King, who has repeatedly and recklessly called for the prosecution of various journalists over the last decade, said Greenwald should be charged with a crime based on alleged comments that Greenwald never made. No one else in Congress has called for any reporters to be prosecuted as part of the recent NSA revelations.

More worrying than Gregory’s question, however, was the insinuation that Greenwald’s reporting isn’t journalism. “The question of who’s a journalist may be up to a debate as to what you’re doing,” Gregory said in response to Greenwald’s answer. He also defended himself later in the show, saying, “There’s a question about [Greenwald’s] role in this, The Guardian’s role in all of this.”

There are serious implications to questioning the status of journalists based on their opinions. Was Edward R. Murrow not a journalist when he reported on, and advocated against, the McCarthy witch hunts in the 1950s? What about when Walter Cronkite advocated, on CBS Evening News, for the end of the Vietnam War? Should his subsequent reports, perhaps influenced by his opinion, not be considered journalism?

When Sen. Claire McCaskill questioned Greenwald’s agenda in reporting these stories, Greenwald didn’t deny it. He responded, “Yes…we have an "agenda" - it's called "transparency" - the same [agenda] Obama/2008 said he had.”

The reality is that there aren’t any journalists on earth that do not naturally have opinions on the subjects they cover. Some choose to hide those opinions behind the veil of “objectivity” as much as possible, others do not.

But regardless of one’s choice of reportage, no journalist loses his or her “objectivity” by defending the principles of transparency or the protections afforded to them under the First Amendment. Indeed, it is built into their job description.

Pulitzer Prize winner Barton Gellman, who reported on PRISM for the Washington Post and has access to some of the Edward Snowden’s documents, put it succinctly: “My advocacy is for open debate of secret powers,” he said. “That's what journalists do.” As the 19th century British publisher Lord Northcliffe once said, "News is what somebody somewhere wants to suppress; all the rest is advertising."

The First Amendment was written to enable that adversarial spirit, to protect the journalists who report on the government’s secrets, and to preserve a transparency safety-valve for citizens when their government fails to inform them of actions done under their name.

Journalists endanger their own rights when they don’t stand up for others in their profession, regardless of their point of view. If Glenn Greenwald were ever prosecuted, there would be nothing stopping the Justice Department from going after journalists like David Gregory next.