The Senate Armed Services Committee on Thursday approved an amendment to its 2022 defense policy bill that would expand the Selective Service System by requiring women to register for the draft.

The amendment to the Military Selective Service Act was approved by a committee vote of 21-5, with five Senate Republicans opposed, according to Politico reporter Burgess Everett. Eight Republicans on the committee voted in favor of the amendment, which is now attached to the 2020 National Defense Authorization Act, a piece of legislation generally considered by lawmakers to be "must-pass."

Five Senate Republicans opposed expanding registering for the Selective Service/potential draft to women. Hawley a… https://t.co/LYICwx63rB

— Burgess Everett (@burgessev) 1626970681.0

The language changing the Selective Service System was authored by Armed Services Committee Chairman Sen. Jack Reed (D-R.I.), Politico reported. His amendment expands Selective Service registration to "All Americans" and strikes explicit references to males.

In 2015, the Obama administration acted to remove all gender-based restrictions on military service beginning in January 2016. At the time, Armed Services Committee Chairmen Rep. Mac Thornberry (R-Texas) and Sen. John McCain (R-Arizona) released a joint statement calling on Congress to review the implications of the Obama administration's decision and examine "any changes to the Selective Service Act that may be required as a result of this decision."

With all combat roles open to women, some have argued that there is no reason women should be exempt from conscripted service. Last year, the National Commission on Military National and Public Service recommended that women be made eligible for the draft after being tasked by lawmakers to investigate the matter.

Adult males ages 18-25 are required by law to register with the Selective Service System for conscripted military service in times of war. America's last draft ended in 1973, at the conclusion of the war in Vietnam, and the U.S. military has relied on an all-volunteer force since then.

Last month, the U.S. Supreme Court declined to take up a case challenging the constitutionality of excluding women from the draft. The Court said that Congress, which holds the constitutional power to raise armies and navies, is ultimately responsible for setting conscripted service policy and noted that lawmakers were already debating the matter.

"It remains to be seen, of course, whether Congress will end gender-based registration under the Military Selective Service Act," Justice Sonia Sotomayor wrote in an opinion joined by the other liberal justices. "But at least for now, the Court's longstanding deference to Congress on matters of national defense and military affairs cautions against granting review while Congress actively weighs the issue."

Whether women should be required to register for the draft has been debated in Congress several times, but this is the first time an amendment extending Selective Service registration to women has passed out of committee. In the past, several Republican members of the Armed Services Committee have supported such efforts, including Sens. Deb Fischer (R-Neb.), Joni Ernst (R-Iowa), Thom Tillis (R-N.C.), Dan Sullivan (R-Alaska), and Lindsey Graham (R-S.C.). Others, mostly conservatives, have led the opposition.

"Our military has welcomed women for decades and are stronger for it. But America's daughters shouldn't be drafted against their will," Sen. Tom Cotton (R-Ark.) said in a statement after the vote. "I opposed this amendment in committee, and I'll work to remove it before the defense bill passes."

"It should be our political mission to defeat any member of Congress (Senate or House) in either party who forces this garbage on our daughters. This is a non-starter, and is all out political war," Rep. Chip Roy (R-Texas) declared on Twitter, tagging Senate Minority Leader Mitch McConnell (R-Ky.) and House Minority Leader Kevin McCarthy (R-Calif.).

It should be our political mission to defeat any member of Congress (Senate or House) in either party who forces th… https://t.co/TZo0mFSNfI

— Chip Roy (@chiproytx) 1627012905.0

"This is it for me. This is a litmus test. Fight this nonsense or we are not on the same team. Abolish the draft if you want ... but draft my daughter you will not," Roy, a member of the House Freedom Caucus, said in a follow-up tweet.

His fierce opposition to drafting women into the military is shared by conservative grassroots leaders.

"Only a wicked and cowardly nation would conscript its daughters into war. Democrats pushing this initiative are wicked and the Republicans who failed to oppose it are cowards," Terri Schilling, president of the American Principles Project, said.

"Republicans who vote to draft our daughters cannot be relied upon to oppose any other harmful items of the Left's woke agenda. Americans oppose the harmful policies of the Democratic Party, but they also don't trust Republicans in effectively opposing the Left's agenda because of moments like this," Schilling added.

"On top of this being harmful to America, it's also incredibly stupid politics. You don't need to be Karl Rove to know that attacking Democrats for conscripting our daughters would be politically beneficial heading into the most crucial midterm elections in recent history. With Republicans like this, who needs Democrats? Thank God for leaders like Sens. Josh Hawley and Tom Cotton for having the stones and brains to stand up against this insane agenda."

Russ Vought, president of the Center for Renewing America, simply commented "No. You are not drafting our daughters."