“Don’t ask, don’t tell” officially comes to end September 20. And while the controversial ban on gay men and women serving openly in the US military no doubt will continue to be the subject of social and political debate, the change in policy comes as public attitudes have shifted dramatically since DADT came into force 18 years ago.

Many gay elected officials, newscasters, sports figures, and other prominent public figures no longer feel the need to be closeted. Six states now allow same-sex marriages. And public attitudes toward LGBT (lesbian, gay, bisexual, and transgender) Americans have moved toward greater tolerance – particularly among younger generations.

Between 1996 and 2011, according to Gallup, the percentage of those polled who think marriages between same-sex couples “should be recognized by the law as valid, with the same rights as traditional marriages” has doubled to 53 percent. Meanwhile, the percentage that thinks such marriages should not be valid has dropped from 68 percent to 45 percent.

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On Friday, President Obama formally certified that the US military is ready to accept those in uniform regardless of sexual orientation. The day before, Defense Secretary Leon Panetta and Chairman of the Joint Chiefs of Staff Admiral Mike Mullen both signed off on the certification as well.

“Service members will no longer be forced to hide who they are in order to serve our country,” President Obama said in announcing an official end to DADT in 60 days (Sept. 20, 2011). “Our military will no longer be deprived of the talents and skills of patriotic Americans just because they happen to be gay or lesbian.”

In recent months, some two million service members have received training in how to handle the new policy.

“It remains the policy of the Department of Defense that sexual orientation is a personal and private matter,” said Clifford Stanley, undersecretary of defense for personnel and readiness and a retired Marine Corps major general. “There will be zero tolerance for harassment, violence or discrimination of any kind.”

Still, an end to DADT will require some adjustment as more gay Americans are drawn to military service and serve openly – particularly in close quarters. The military is not allowed to provide segregated living facilities.

For those who lived and served through an earlier time when homosexuality in the military was grounds for immediate dismissal (if not prosecution), the change in policy comes as a long-sought victory.

“Certification that our military will not be harmed by allowing gay Americans to serve without restrictions closes a long, sad chapter for the many military men and women who have coped with an appallingly discriminatory, wrongheaded US policy,” says Beth Coye, a retired US Navy commander and author of “My Navy Too,” a novel based on her own experiences. “With this policy change we will be a stronger, more just land – a land of the free and the brave, whatever one's sexual orientation.”

At the same time criticism of the new policy continues.

“History will hold accountable President Obama, members of the previous lame-duck Congress, and gay activists who misused the federal courts in order to impose LGBT law and policies that will undermine morale and readiness in the All-Volunteer Force,” said Elaine Donnelly, president of the Center for Military Readiness, which fought an end to DADT.

The end of DADT comes against the backdrop of other recent advances in gay rights. On Sunday, New York will become the largest state to begin holding same-sex marriages. The Obama administration is pushing to end the Defense of Marriage Act (DOMA). Maryland Gov. Martin O’Malley (D) says he will now make legalizing same-sex marriage one of his top priorities.

“This is an evolution in the progress of our state, to be able to perfect our laws so that they more fully protect the rights of every individual,” Gov. O’Malley – whose Catholic upbringing once led him to believe that marriage had to be between a man and a woman – said Friday.

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