With the release of the Pentagon’s report on “Don’t Ask, Don’t Tell,” will Sen. John McCain and his fellow resisters man up, do the right thing, join the 21st century (as well as every other Western country), and let homosexuals openly enlist in the military?

Certainly the report’s findings leave little room for continued stalling on the issue.

McCain, the senior Republican on the Senate Armed Services Committee, said a few years ago that he would consider repealing DADT once the senior military leadership endorsed doing so. When Secretary of Defense Robert Gates and Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, did just that earlier this year, McCain said he would await the results of a Pentagon study that had been commissioned.

When the study came out on Nov. 30, concluding that repeal would carry “low” risks for any measure of military effectiveness, McCain said he needed to question the officers who actually command troops—which (with all due respect) neither Gates nor Mullen directly does—especially the service chiefs, including the commandant of the Marine Corps (who had already spoken out against repeal).

In persisting with this charade of bigotry disguised as prudence, McCain sidesteps the fact that the repeal of DADT has publicly been endorsed by his very own favorite officer, Gen. David Petraeus—who has been the commander of both the wars, in Iraq and Afghanistan, that U.S. troops have been fighting lately.

Really, senator, what more is there to say?

The 257-page report—dauntingly titled “Report of the Comprehensive Review of the Issues Associated With the Repeal of ‘Don’t Ask, Don’t Tell,’ ” and written by a panel co-chaired by Jeh Charles Johnson, the Pentagon’s general counsel, and Gen. Carter F. Ham, commander of the U.S. Army in Europe—makes the case that McCain and others have been demanding.

Much of the study reports and analyzes the results of a survey sent to 400,000 active-duty members of the armed services (115,052 of whom responded), as well as surveys of more than 40,000 military spouses and several workshop forums and face-to-face interviews.

The top line is that 70 percent of those surveyed say that repealing DADT—and thus working, eating, sleeping, showering, and fighting in the same room or on the same ship, plane, or battlefield with service members who say they’re gay—will have a positive, a mixed, or no effect (in other words, won’t have a bad effect) on accomplishing the mission.

That, of course, is not an entirely reassuring conclusion. It means that 30 percent think it will have a bad effect. In a fighting force built on unit cohesion and trust, 30 percent is a lot.

Broken down by services, the data seem more disturbing still. For instance, among members of the U.S. Marine Corps, 47 percent of respondents think repeal of DADT would have a negative effect on mutual trust within a unit. Among Marines in combat positions, the figure rises to 60 percent. (A similar pattern holds in the Army. Overall, 35 percent of Army soldiers think it would have a negative effect, while 49 percent of Army combat soldiers do.)

McCain and other critics have seized on these numbers to justify a continuation of present policy.

However, as the study spells out, these figures—put in perspective—are less meaningful than they seem. Among members of the armed forces who have actually worked with someone they believe to be gay, 92 percent say that the unit’s effectiveness is very good, good, or “neither good nor poor” (in other words, at very least, not bad). Among Army combat soldiers who have fought alongside someone they think is gay, 89 percent think the experience hasn’t hurt the unit. The same is true among 84 percent of Marine combatants.

As the report puts it, the apparent “misperception that a gay man does not ‘fit’ the image of a good warfighter … is almost completely erased when a gay service member is allowed to prove himself alongside fellow warfighters.” In one of the interviews, a special-operations fighter said, “We have a gay guy [in the unit]. He’s big, he’s mean, and he kills lots of bad guys. No one cared that he was gay.”

Along these lines, the report’s authors conclude that, “in the short term,” repeal of DADT may cause “some limited and isolated disruptions to unit cohesion and retention,” but “we do not believe this disruption will be widespread or long-lasting,” and it can be further diminished through proper leadership and training.

The report notes that only five other countries ban gays in the military: Bulgaria, Jordan, Poland, Turkey, and the United Arab Emirates. Over the last two decades, several countries have reversed their former bans, among them the United Kingdom, Canada, Australia, Germany, and Israel. In Canada and the United Kingdom, surveys taken just before the reversal showed 60 percent to 65 percent of service members opposed the move; many said they would leave the military if the liberalization went through. However, the actual effect on recruitment and retention turned out to be minimal.

In what should be a particularly embarrassing section to the repeal’s opponents, the study draws parallels between DADT and the military’s racial segregation of more than a half-century ago. In a survey of more than 2,000 enlisted men in 1946, more than 80 percent of respondents agreed with the view that “white and Negro soldiers should not work, train, and live together.” About 80 percent of white officers said they would not want to be assigned to a racially integrated unit.

That was at a time when American society was deeply segregated. (President Harry Truman’s act of integrating the Army truly was a social experiment.) And, of course, a soldier’s skin color is obvious whereas, even after the repeal of DADT, a gay soldier can stay in the closet. (The Pentagon report cites a separate survey by the RAND Corp. in which only about 15 percent of gay servicemen and women say they’ll come out, even after their open presence is legally permitted.)

The impulse to repeal DADT is not just a question of human rights or morality; it’s also a matter of national security. Since 1980, according to the report, more than 32,000 active-duty servicemen and women have been discharged because of their homosexuality—13,000 of them since 1993, when the DADT law went into effect. (By the way, 85 percent of them simply announced that they were gay; only 15 percent were booted out for their behavior.)

These figures aren’t huge; they amount to a little less than 1 percent of all involuntary discharges in that period. But the losses are larger than gross percentages might suggest. From 1995 to 2003, according to a report at the time by the Government Accountability Office, the military canned 322 service members who had skills in a foreign language that the Pentagon deemed important, simply because they were homosexual; 209 of them had been trained in that language at the Defense Language Institute.

In the last five years, according to data compiled by the Servicemembers Legal Defense Network, the military has discharged more than 800 troops in “mission-critical” slots, at least 59 Arabic linguists and nine Farsi linguists, for violating “Don’t Ask, Don’t Tell.”

The evidence, the polling data of service men and women, the testimony of senior officers, the everyday experiences of living and fighting, the imperatives of national security, as well as the obvious moral standards of contemporary life—all point to, at the very least, a shift in the burden of proof on whether DADT should be repealed. It’s no longer valid, and it’s clearly a pretense, to call for further studies, further surveys, closer questioning. If McCain and the others oppose repeal, they have to come up with some new reason—or fall back on the oldest, most unpalatable reason—why.

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