After learning of a number of bomb threats aimed at the Washington D.C. area, federal authorities have arrested Facebook user Sundullah Ghilzai, who allegedly boasted on the social network that he'd use explosives in the city's public transit system.

But for all our complaints of Facebook's privacy issues and ability to mine our personal data, it still took an informant to catch Ghilzai.

YouTube moved this week to allow users to flag videos that potentially promote terrorism. Should Facebook be combing its network for this type of behavior?

According to his arrest warrant, Ghilzai (who also may go by Awais Younis or Mohannme Khan) allegedly posted a variety of photographs and messages that could've provided hints into his intentions. In one image, he reportedly stands holding an AK-47 in front of a tent filled with explosives. The caption underneath read, "My family business." In another post, he is said to have written, "Christmas trees were going to go boom."

Details are still scant, but the most explicit threats allegedly came during an online chat with an acquaintance, who at some point turned Ghilzai in to authorities. Still, were there public details that should've raised red flags earlier?

On what appears to be Ghilzai's Facebook page, above—click to expand—his activities include "AK-47." (Messages sent to the owner of the page via Facebook and an associated e-mail address were not immediately answered.) But other than a few similar indicators, his page is innocuous (interests in artists Nicki Minaj and band The Afghan Whigs and the movie "Red Dawn," "Top Gun," and "War Games" are completely understandable). And according to the page, he worked as a summer associate in public outreach and education for the US Department of the Interior.

Only last week, the FBI themselves caught on to the jihadist Facebook boasts of a 21-year-old Baltimore construction worker and arrested him, claiming he planned to blow up a military recruitment center. Facebook itself did not appear to be involved.

The underlying question is: Would be willing to sacrifice even more online privacy in order to monitor for potential threats like this? If we allow third-parties and advertisers to mine our cookies and personal data, would we be willing to allow federal authorities and Facebook to scan our social networks for warning signs?

Republished with permission from FastCompany.com. Authored by Austin Carr. Screenshot via Fast Company.