Not even Democrats seem all that impressed with a veto threat from Barack Obama these days. When the White House leaked that it would abandon executive-order strategies to close the detention center at Guantanamo Bay, it had to know that no other path would remain open. A Senate vote today removed all doubt. On an 85-13 vote, the upper chamber overwhelming passed a national defense authorization act (NDAA) that slams the door shut on transfers of terrorist detainees to the US:

Defying a White House veto threat, the Senate voted decisively Tuesday to approve a defense policy bill that authorizes $602 billion in military spending, bars shuttering the prison at Guantanamo Bay, Cuba, and denies the Pentagon’s bid to start a new round of military base closings.

The GOP-led Senate’s version of the National Defense Authorization Act passed 85 to 13, with all but seven members of the Democratic caucus backing the legislation. Six Republicans voted against the bill.

The NDAA ended up with 39 Democrats backing it. If Obama does issue a veto, it would only take 13 Democrats to overcome it, assuming Republicans in the Senate fell in line. If not, then it would take 19 of the Democrats who voted for the bill to override the veto — less than half of its current support.

The only real dark cloud on the horizon will be the conference committee with the House, whose version has a couple of significant differences. Forcing Gitmo to remain open is not one of them, but a new requirement for women to register for the Selective Service could make the final bill more vulnerable to a veto:

The legislation mandates for the first time in history that young women sign up for a potential military draft. The requirement has angered social conservatives, who fear the move is another step toward the blurring of gender lines akin to allowing transgender people to use public lavatories and locker rooms. …

The Republican-led House passed its version of the defense bill last month and lawmakers from both chambers must meet in a conference to resolve differences. The House, for example, excludes the female draft requirement and seeks $18 billion more in spending than the Senate to pay for troops and weapons the Pentagon didn’t request.

There may be some in the social-conservative caucuses who argue against drafting women on the basis of a slippery gender slope. However, most of the arguments made on that issue deal directly with whether women can handle combat duties as well as men, and how women in combat might impact unit readiness and performance. For most opponents, it comes down to a fundamental philosophy and tradition that values the defense of women, while advocates see it as an equality issue.

Much of that argument is hypothetical in both directions, but some allies (notably Israel) have drafted or enlisted women to serve in combat roles for some time. In Israel, at least, the policy seems to be a success after the 2004 launch of the co-ed Caracal Battalion:

One question that crops up in the discussion about women is whether men will trust female soldiers with their lives. Prince’s commander, Capt. Yaron Eyal, says he has gotten over any doubts he had.

“I really, really trust them … to watch my back,” he says, relying on Prince to help him find the right English expression.

Israel holds out the Caracal as proof that women can be all that they can be in the military. The Israel Defense Forces say that today, nearly 50 percent of Israel’s lieutenants and captains are women.

Those opposed to a new policy for combat roles out of practical concern might be swayed by this, but not those opposed on philosophical grounds.

In any case, this will probably be the most contentious part of the NDAA conference committee. If the joint bill comes with the new registration requirement, it may lose some of the support the House bill had when it passed on a 277-147 vote — short of the 290 needed to overcome a veto, although it might then also pick up some support from House Democrats. If the women-in-combat language gets stripped out, then the bill may lose some Democratic support in the Senate. The question will be just how much there is to lose — and how tough Congress wants to be in dealing with a lame-duck President who’s tossing out veto threats by rote these days.

Update: I used the wrong name for the NDAA. It’s fixed now, and thanks to David K for the correction.