DADTBrendanSmialowski:Getty

Ambinder explains the mechanics of the DADT compromise:

It is a REPEAL with a TRIGGER mechanism. The repeal will be on the books, but policy won't change until certain thresholds are crossed. Those thresholds happen to be the same conditions that Secretary of Defense Robert Gates and Adm. Mike Mullen (C/CJS) had already set -- no impact on readiness, recruitment, effectiveness, retention, and unit cohesiveness. However, repeal will become official policy; not if, but when becomes set in stone. Gates, initially hesitant to upend his timetable, which saw his work being finished in December and repeal early next year, agreed to compromise language. That's because Gates gets to make the final call as to when. There appears to be enough votes in the Senate to add this provision to the defense appropriations markup. The House might add language THIS WEEK. A victory for gay rights groups who had been pushing Congress and the White House to act more quickly; key players include Sens. Lieberman, Levin, Rep. Murphy, Speaker Pelosi and deputy chief of staff Jim Messina, in whose hands the president delegated the task.

Dale Carpenter adds:

The repeal is limited in one sense. It does not ban discrimination against gays in the military. It returns the status quo ante DADT in 1993 when the president had sole authority to set military personnel policies on gays. The difference is that now the president has promised to reverse the old policy after a study is issued in December on how to implement the change. 

In theory, the next president could reassert the ban. But that’s very unlikely to happen once gays are serving openly. Liberalization of anti-gay public policy tends to be governed by one-way ratchet. Plus, the experience in other countries has been that allowing service by openly gay personnel presents no real problems for recruitment, retention, or discipline, and controversy about it quickly subsides.

And Drum zooms out:

So if things go the way I think they'll go, by later this year Obama, Pelosi, and Reid will have passed a historic stimulus bill, the Lily Ledbetter Act, healthcare reform, college loan reform, financial reform, repeal of DADT, and Obama will have withdrawn from Iraq.1 Not bad for 18 months of work. And who knows? There's even a chance that Obama's Afghanistan escalation will work. If it does, what president since LBJ will have accomplished more in his first term?

1Except for the pesky "residual force," of course. Still, once the combat forces are gone, it's hard to see a scenario in which they're ever sent back in.

My major fear up to now has been that the repeal could get lost legislatively if the GOP made big gains in the House and Senate this fall, as is historically almost certain. This compromise removes the basis for that fear, while allowing the military and the defense secretary to manage the transition to ensure a smooth ride. I hope it works. If it does, it really will be a feather in the cap of Jim Messina, the good folks at SLDN and Servicemembers United, and the Obama administration. It will also redound to the credit of those who did not give up on this, who refused to concede that this was not a civil rights question of the first order, and to the countless servicemembers, past and future, who put their lives and careers on the line for this change.

It's been a long two decades. So long one almost feels numb at exactly the moment one should feel exhilarated. But that's probably how all such breakthroughs feel, when they eventually happen. For the first time in American history, gay people will be deemed fully worthy of the highest call of patriotism - to risk one's life for the defense of one's country.

In that sense, for the first time, the Congress and president will treat them as fully citizens.

(Photo: Former Coast Guard Academy Cadet Bronwen Tomb (L), who was removed after telling another cadet she was gay, former Air Force Staff Sgt. David Hall (C), who was removed from the Air Force Academy after being accused of but not admitting to being gay, and Navy Capt. Joan Darrah, who served as a lesbian, listen during a news conference on Capitol Hill March 3, 2010 in Washington, DC. U.S. Sen. Joseph Lieberman (I-CT) has introduced legislation to repeal the U.S. military's don't ask don't tell policy for gays and lesbians serving in the military. By Brendan Smialowski/Getty Images.)

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