A measure in the National Defense Authorization Act meant to keep white nationalists out of the U.S. military no longer mentions “white nationalists” after Congress quietly altered the text after it initially passed the House.

The change, which has not been previously reported, could water down a House-passed amendment meant to address the threat of white nationalists in the military. The House language was specifically drafted to encourage screening for white nationalist beliefs in military enlistees. But after the Republican-controlled Senate passed its own version of the massive military spending bill and the two chambers’ bills were reconciled, the final NDAA instead requires the Department of Defense to study ways to screen military enlistees for “extremist and gang-related activity.”

While it may seem like a minor tweak, the removal of the term “white nationalists” from the amendment text was concerning to Rep. Pete Aguilar (D-Calif.), who introduced the amendment in July after alarming reports about white nationalists in the U.S. military.

Earlier this year, federal authorities arrested a Coast Guard lieutenant for allegedly stockpiling weapons in preparation for a terror attack. A series of HuffPost investigations also exposed 11 U.S. service members who had ties to Identity Evropa, a white nationalist group best known for helping organize the deadly 2017 “Unite The Rally” in Charlottesville, Virginia.

Stripping the specific mention of “white nationalists” from the legislation could leave the door open for more white nationalists to join the military and could leave the U.S. military off the hook for what many critics say are lackluster efforts to screen enlistees for white nationalist beliefs.

We cannot turn a blind eye to this growing problem which puts our national security and the safety of the brave men and women serving our country in jeopardy. It’s disappointing that Senate Republicans disagree. Rep. Pete Aguilar (D-Calif.)

It’s not clear who approved the language change or why. Senators on the U.S. Senate Armed Services Committee, including Chairman Jim Inhofe (R-Okla.), did not respond to HuffPost’s requests for comment on the language.

After the House and Senate each passed their own versions of the NDAA, lawmakers from both chambers met to reconcile differences between the two. The final NDAA was then approved by both chambers.

Aguilar said the fact that the final NDAA does not mention “white nationalism” indicates the Senate may not be taking white nationalism seriously.

In a statement to HuffPost, he noted that white nationalists have “successfully enlisted in our military in order to gain access to combat training and weaponry.”

To prevent more white nationalist violence, Aguilar said, “we cannot turn a blind eye to this growing problem which puts our national security and the safety of the brave men and women serving our country in jeopardy.”

“It’s disappointing that Senate Republicans disagree,” he added.

© LUKE MONTAVON via Getty Images Rep. Pete Aguilar (D-Calif.) speaking at a press conference in July 2019.

Academics and law enforcement officials have long warned of the specific threat posed by white nationalists who join the military, where they receive combat training they can use to inflict violence on civilians. White supremacists have long been attracted to the U.S. military, and often for good reason. In the 1970s, for example, a Department of Defense directive allowed service members to join the Ku Klux Klan.

Although military rules prohibit service members from committing acts of discrimination or engaging in extremist activity, an unnerving 2017 Military Times poll found that nearly 25% of American service members reported encountering white nationalists within their ranks.

Just this week, an ESPN article revealed the Army football team’s motto had origins in the neo-Nazi gang the Aryan Brotherhood; two cadets flashed the “OK” hand sign, often a white power symbol, on live television during the Army-Navy football game; and Army units memorialized World War II’s Battle of the Bulge on social media by posting a photo of a Nazi war criminal.

Last month, Vice News confirmed that three members of the U.S. military were registered users of the online neo-Nazi forum Iron March.

And in 2018, a series of investigative reports by ProPublica and “Frontline” found multiple members of violent neo-Nazi groups in the armed services.

Aguilar’s amendment to the NDAA this year sought to address this long-standing problem by requiring the Secretary of Defense to “study the feasibility” of screening for “individuals with ties to white nationalist organizations” during initial background investigations of enlistees.

The amendment also requires the Department of Defense to study whether two FBI resources — the Tattoo and Graffiti Identification Program and The National Gang Intelligence Center — could aid the military in this effort.

CLARIFICATION: This piece has been updated to add further information on the NDAA passage process.

This article originally appeared on HuffPost