President Barack Obama signs the Don’t Ask, Don’t Tell Repeal Act of 2010 lifting the ban on homosexuals serving openly in the U.S. armed forces at the Department of the Interior in Washington, Dec. 22, 2010.

*Surrounded by senior military officials and members of Congress, President Barack Obama signed a landmark law ordering America’s armed services to allow gay men and women serve openly for the first time.

“For we are not a nation that says, ‘don’t ask, don’t tell,'” Obama told 500 guests at a signing ceremony at the Interior Department. “We are a nation that says, ‘Out of many, we are one.’ ”

As they applauded his arrival, Obama told them he was “overwhelmed” and that it was a “very good day.” He thanked the lawmakers who worked on the legislation but saved his warmest praise for the leaders of the Pentagon and the troops themselves.

“History will remember well the courage and vision of Secretary Gates, of Admiral Mike Mullen, who spoke from the heart and said what he believed was right,” Obama said.

The change won’t be immediate, however. The bill requires the military service chiefs to complete implementation plans before lifting the old “don’t ask, don’t tell” policy — and certify to lawmakers that it won’t damage combat readiness, as critics charge.

But Obama promises, “We are not going to be dragging our feet to get this done.” He said that years from now, people will wonder “why was there ever a source of controversy in the first place.”

Gay troops fought at Gettysburg and at Iwo Jima, Obama said. “Their names are etched into the walls of our memorials. Their headstones dot the grounds at Arlington,” he says. “So as the first generation serving openly in our armed forces, you will stand for all those who came before you. You will serve as role models for all who come in. I know you will fulfill this responsibility with integrity and honor, just as you have every other mission.”

Obama added: “Your country needs you. Your country wants you. And we will be honored to welcome you into the ranks of the finest military the world has ever known.”

When he visited Afghanistan a few weeks ago, Obama recalled, a woman grabbed him in a rope line and whispered to him, “Get ‘don’t ask, don’t tell’ done.” He said he told her, “I promise you, I will.”

“For we are not a nation that says, ‘don’t ask, don’t tell,’ ” he said. “We are a nation that says, ‘Out of many, we are one.’ We are a nation that welcomes the service of every patriot. … It is my honor to sign this bill into law.”