The amendment, sponsored by Rep. Brad Schneider, was passed in a 218-208 party-line vote on Wednesday.
All 208 votes against the amendment came from House Republicans, one of whom described it as "Orwellian.".
The amendment called for the total number of people who were discharged from the military or police because of their links to or support for far-right extremism to be published.
There is no reason to believe that our military is any different," Schneider said during debate on the House floor.
Arizona GOP congressman Andy Biggs was one of those who spoke out against the amendment, describing it as "Orwellian in nature.".
The update included supporting the overthrowing of the government and "liking" or sharing extremist views on social media.
Last February, the Pentagon released another report warning of the prominence of white supremacist ideology inside the military. »