Coming up on 'This Week'… Don't Ask Don't Tell Debate

Plus, Afghanistan: Can We Win?

WASHINGTON, Dec. 2, 2010— -- A new Pentagon report concludes that the risk to military readiness if Don't Ask, Don't Tell were repealed would be low, but Senate Republicans are vowing to block efforts to allow gays to serve openly in the military. Sunday morning, Christiane Amanpour brings all sides together for a powerful "This Week" debate.

• Former NATO Supreme Allied Commander Wesley Clark has led men in battle and supports the repeal.• Lt. Col. (ret.) Bob Maginnis is Senior Fellow of the Family Research Council and served as an advisor to the 1993 Military Working Group that examined the issue of gays in the military. He opposes the repeal and believes the Pentagon study was flawed. • R. Clarke Cooper, Executive Director of the Log Cabin Republicans which is challenging DADT in the courts. Cooper is an active duty army reservist who served in Iraq. • Elaine Donnelly of the Center for Military Readiness says repealing DADT would cause major problems for the military and is part of a political agenda. • Tammy Schultz, Director of National Security and Joint Warfare at the Marine Corps War College who teaches Marines at Quantico and offers her insight into why the Marine Corps is the most resistant service branch to changing DADT.

Then, nine years into the war in Afghanistan, ABC News looks at the critical question, can we win? Top voices on the war, including former National Security Adviser Zbigniew Brzezinski, former ambassador to the United Nations and Afghanistan Zalmay Khalilzad, Sakena Yacoobi of the Afghan institute of Learning and George Will look at that question and debate what victory looks like.

Is there a way out of the conflict? Has the war made America safer? Can the U.S. work with a corrupt government and can deals be cut with the Taliban? Part of an ABC News special week of coverage – Afghanistan: Can We Win? – Sunday on "This Week."