It’s been two generations since “your number is up” meant anything but relief at the DMV or a one-way ticket to the pearly gates.

But for any man older than 65, it once meant something entirely different. It was your draft number, whether it be your birthday (Vietnam) or your district number (WWII). The information was pushed into a capsule no bigger than a cyanide pill, which was tossed into a fishbowl filled with hundreds or thousands of other tiny blue orbs. On “lottery day,” one capsule was plucked from the others. When a man’s number was “up,” he reported to the draft board and, if deemed fit for duty, was thrown into war.

Those were all the able-bodied men in a certain age range. Now imagine young women sitting in front of their televisions, or glued to their mobile devices, waiting to see if their numbers are up. It seems fantastical, 40 years after the draft was ended and with an all-volunteer force now filling the ranks for war. But the issue of whether to open the Selective Service to women—all men 18-25 are still required to register—is very much a debate on Capitol Hill today.

In fact, such a change could be included in the next major defense budget authorization bill.

Despite the unlikely nature of a draft, it is a salient issue that has split both Democrats and Republicans. It’s shaken their political sensibilities around and settled them down on either side in unlikely alliances. Presidential candidates have even had to address the question in primary debates.

In one corner, there are champions of women in the military, where the ranks have recently opened combat roles to female soldiers. For them, equality is a goal that cannot and should not be deterred by something as unpopular or archaic as the draft. If women want parity in the military, it starts here. It’s symbolic.

On the other side, there are two factions. One thinks women should not be in combat and therefore would overburden a draft board with deferments and disqualifications—a silly, bureaucratic nightmare born out of political correctness. The other school thinks the draft should be eliminated entirely, and lining up women to serve it, no matter how symbolic, is an anathema. Let the volunteer force—whether it be men or women—fight, if the country must defend itself.

Military historian Andrew Bacevich calls it a “tempest in a canteen cup,” and he is probably right: The draft was eliminated in 1973 for a reason. Despite the fact the Vietnam War was winding down, he writes, it was the conscription of tens of thousands of young men during that conflict that “spurred anti-war sentiment and benefited no one—apart perhaps from Canada, favored destination of many thousands of draft evaders.”

That may be, but how we came to be talking about opening the Selective Service to women today is significant in itself, and probably speaks about heightened tensions involving women in combat more than anything else.

It began when Rep. Duncan Hunter (R-Calif.), an Iraq War veteran, first proposed an amendment in April opening the draft to women in the House National Defense Authorization Act (NDAA). The move came not as a symbol of women’s growing equality in the forces, mind you, but as a “gotcha,” according to Politico. He wanted to underscore the problematic nature of that newly enforced equality.

“In a marathon session to craft a new defense policy bill, the panel backed Rep. Duncan Hunter’s amendment by a 32-30 vote,” reporter Connor O’Brien wrote on April 28. But “by his own admission, however, the California Republican does not actually intend to include women in a draft and voted down his own amendment.” He opposed opening up all combat units to women and was clearly using the amendment to show that “colleagues have failed to fully account for the implications of the shift.”

“I’ve talked to coffeehouse liberals in San Francisco and conservative families who pray three times a day,” Hunter said during the markup of the NDAA. “And neither of those groups want their daughter to be drafted.”

He is right, of course, but he failed to note that there are also stalwart constituencies for drafting women, including the Pentagon brass. Both Army Chief of Staff Mark A. Milley and Marine Corps Commandant Robert Neller have said publicly that if women are in combat, women must be in the draft. While this may not sound like a rousing endorsement (the Marines, after all, were the last to come around to the changes), their backing has ignited support among the hawks on the Hill.

That includes head hawk Sen. John McCain (R-Ariz.), who is typically considered one of the the most pro-military (if not pro-war) members of Congress. He offered his own amendment drafting women for the Senate version of the NDAA on May 10.

“As women serve in more roles across the armed forces, I support the recommendation of the Army Chief of State and the Commandant of the Marine Corps that women should register for Selective Service,” McCain said in a statement to Roll Call on May 12. “It is the logical conclusion of the decision to open combat positions to women.”

He is joined by fellow hawk Sen. Kelly Ayotte (R-N.H.), who in February said that after hearing from military officials, she too was convinced that “it makes sense that … women would also register for the Selective Service.” Her colleague Sen. Marco Rubio (R-Fl.) expressed the same sentiment during a New Hampshire presidential primary debate. “I have no problem whatsoever with people of either gender serving in combat so long as the minimum requirements necessary to do the job are not compromised,” he said. Having gained access to combat, “I do believe that Selective Service should be opened up for both men and women in case a draft is ever instituted.” (He flip-flopped almost immediately.)

Now, these Republicans may be exhibiting the same kind of cynicism as their colleague Duncan: Everyone knows the draft itself is as unpopular as a skunk at a picnic, and that we will likely never see the likes of it again—so why not support opening the Selective Service to women on the merits of the idea, at least winning points with the millions of women who support it?

Or perhaps it is just a subtler form of the answer military writer Michael Yon gave TAC when we asked him.

This is a no-brainer. If women wish to try out for Rangers, SEALS, Green Berets, they wish for equality,” said Yon, who served in special forces in the 1980s. “Draft them if needed. Put up or shut up.”

But such condescension isn’t likely to thwart the women who are already expressing an interest in “putting up,” and unlike Duncan, they aren’t bluffing. And they are backed by Democrats like Sen. Claire McCaskill of Missouri, who is usually on the other side of McCain when it comes to military issues.

“The fight for equality and treatment must also include equality in obligation. As we move towards a formalized role for women in combat arms, this is a necessary progression,” said Tyler Gately, a spokesperson for Iraq and Afghanistan Veterans of America (IAVA), which “applauds” the House and Senate for taking up the issue.

“I’m in favor of drafting women. As a female veteran who voluntarily enlisted, I see the importance of civic duty and giving back to our country. Freedom is not free,” says IAVA member De’Cha LeVeau, in an email to TAC. “As women we must step up to the plate, per se. If we are expecting equality; this equality comes with added responsibility.”

Those who have been against women in combat from the beginning—and this fight has been ongoing for decades—have seen enormous changes over the last few years, including special-forces roles opening to both genders. In fact, after passing the grueling trials, three women were the first to earn their U.S. Army Ranger tabs last fall.

But critics insist women do not have the physical capacity to join their male counterparts on the front lines. To achieve parity, the warning goes, women will likely be held to different standards, and this will hurt unit cohesion and readiness. Many of these critics are also social conservatives who blame feminism and political correctness for the drive to include women in the combat ranks in the first place.

“Political correctness is dangerous, and the idea that we would draft our daughters, to forcibly bring them into the military and put them in close contact—I think is wrong, it is immoral, and if I am president, we ain’t doing it,” Sen. Ted Cruz (R-Texas) charged in February, when he was still on the campaign trail.

Meanwhile, a contingent of military women backed by longtime critic Elaine Donnelly at the Center for Military Readiness, are standing firm against what they are calling Duncan’s folly.

“Military women average two to ten times men’s injuries—this means an even higher turnover where the physical demand and intensity is much, much greater, in combat units during war time,” said Jude Eden, an Iraq War Marine Corps veteran, who cited a nine-month study by the Marines released in September.

“Because of these greater liabilities, drafting women will result in more lives being lost unnecessarily when they’re actually replacing infantrymen in a national emergency,” said Eden, who has written extensively on the subject. “The draft isn’t to collect people for desk jobs to ‘free a man to fight,’ it’s to replace the men dying at the front of the fight.”

But there is also the question over whether not opening the draft to women is even legal. In 1981, several men filed lawsuits alleging that the Military Selective Service Act violates the Due Process Clause of the Fifth Amendment because it requires only men, not women, to register. The Supreme Court upheld the act, but gave women’s exclusion from combat roles as the reason for doing so. The ruling may no longer apply now that all the barriers are down.

The wheels of the justice are already turning on the subject: The National Coalition of Men, which has launched a lawsuit similar to the one filed more than 30 years ago, won a recent victory. The 9th Circuit Court of Appeals said their challenge against the Selective Service could go forward, mainly because the changes in policy in Washington made it “ripe for adjudication.”

So why not just get rid of Selective Service altogether? There is a bipartisan group of lawmakers trying to do that, too.

“Not only will abolishing the Selective Service save the U.S. taxpayers money, it will remove an undue burden on our nation’s young people,” Rep. Peter DeFazio (D-Ore.), said in a statement as he and others introduced a bill to end Selective Service in February. “We need to get rid of this mean-spirited and outdated system and trust that if the need should arise Americans—both male and female—will answer the call to defend our nation.”

After the initial dust up, the House Rules Committee ended up pulling Duncan’s draft amendment from the draft NDAA last week. But the Senate continues to contemplate it as final legislation goes forward, folly or no folly.

Kelley Beaucar Vlahos is a Washington, D.C.-based freelance reporter and TAC contributing editor. Follow her on Twitter.