The advancement of human rights around the world was a cornerstone of foreign policy and U.S. leadership for decades, until the attacks on our country on Sept. 11, 2001.

Since then, while Americans continue to espouse freedom and democracy, our government's abusive practices have undermined struggles for freedom in many parts of the world. As the gross abuses at Abu Ghraib and Guantanamo Bay were revealed, the United States lost its mantle as a champion of human rights, eliminating our national ability to speak credibly on the subject, let alone restrain or gain concessions from oppressors. Tragically, a global backlash against democracy and rights activists, who are now the targets of abuse, has followed.

The advancement of human rights and democracy is necessary for global stability and can be achieved only through the local, often heroic, efforts of individuals who speak out against injustice and oppression — endeavors the United States should lead, not impede.

If the early warnings of human rights activists had been heeded and tough diplomacy and timely intervention mobilized, the horrific, and in some cases ongoing, violence in Bosnia, Rwanda, Sudan's Darfur region and the Democratic Republic of the Congo might have been averted.

This week marks the 60th anniversary of the Universal Declaration of Human Rights. With a new administration and a new vision coming to the White House, we have the opportunity to move boldly to restore the moral authority behind the worldwide human rights movement. But the first steps must be taken at home.

President-elect Barack Obama has pledged to shut down the detention facility at Guantanamo Bay and end torture, which can be accomplished by executive orders to close the prison and by enforcing existing prohibitions against torture by any U.S. representative, including FBI and CIA agents. The detention of people secretly or indefinitely and without due process must cease, and their cases should be transferred to our courts, which have proved their competence in trying those accused of terrorism. Further, a nonpartisan expert commission should be named to conduct a thorough review of U.S. practices related to unwarranted arrest, torture, secret detention, extraordinary rendition, abandonment of habeas corpus and related matters. Acknowledging to the world that the United States also has made mistakes will give credence to our becoming "a more perfect union" — a message that would resonate worldwide. Together, these actions will help us restore our nation's principles and embolden others abroad who want higher moral standards for their own societies.

By putting its house in order, the United States would reclaim its moral authority and wield not only the political capital but also the credibility needed to engage in frank but respectful bilateral dialogues on the protection of human rights as central to world peace and prosperity. Human rights defenders around the world, whose annual conference began at the Carter Center this week, are eagerly awaiting the Obama administration. In Pakistan, they look for our help in restoring the rule of law that was undermined when the United States sided with Pervez Musharraf as he debilitated an independent-minded Supreme Court. Defenders of the struggling democratic movement in Egypt seek a tough U.S. stance supporting free and fair elections and ending the abuse of opposition political candidates. Throughout the Middle East, there is hope that the United States will move more aggressively and persistently to help orchestrate a solution to the Israeli-Palestinian conflict, the prism through which the region measures the U.S. commitment to human rights.

In the war-ravaged Democratic Republic of the Congo, rights defenders under daily threat hope the United States will pressure its allies in Rwanda and Uganda to withdraw support from proxy forces that continue to wreak havoc there. All agree that the United States should re-engage with agencies of the United Nations to make that body a more effective tool to protect human rights, knowing that this must be a global effort.

The moral footprint of the United States has always been vast. Our next president has an unprecedented opportunity to lead through example by inspiring and supporting those who would reach for freedom and by being tough and effective with those who would impede freedom's march. All Americans must give him full support.

Jimmy Carter, the 39th president, is founder of the Carter Center, a not-for-profit organization advancing peace and health worldwide. He wrote this commentary for The Washington Post.