(AP Photo/the Guardian, Glenn Greenwald and Laura Poitras, File)

Edward Snowden has one regret about his decision to reveal the inner workings of National Security Agency spying programs: He wishes he did it sooner.

Following Laura Poitras' best documentary win for "Citizenfour" at the Oscars, the filmmaker and Glenn Greenwald, a fellow co-founding editor at Pierre Omidyar-backed news site the Intercept, joined Snowden on reddit Monday to answer questions about the movie and the experience that inspired the film. One person asked Snowden what he would do differently if he had a chance to do it all over again. This was Snowden's response:

I would have come forward sooner. I talked to Daniel Ellsberg about this at length, who has explained why more eloquently than I can.

Had I come forward a little sooner, these programs would have been a little less entrenched, and those abusing them would have felt a little less familiar with and accustomed to the exercise of those powers. This is something we see in almost every sector of government, not just in the national security space, but it's very important: Regardless of how little value a program or power has been shown to have (such as the Section 215 dragnet interception of call records in the United States, which the government's own investigation found never stopped a single imminent terrorist attack despite a decade of operation), once it's a sunk cost, once dollars and reputations have been invested in it, it's hard to peel that back.

Don't let it happen in your country.

Snowden now lives in Russia, where he was granted temporary asylum. But the cache of documents he delivered to journalists continues to provide new scoops about government surveillance programs.