[This Op-Ed was published in USA Today on July 24, 2008. It was retrieved from archives and does not appear to be available on usatoday.com] Recent events have demonstrated clearly that Barack Obama's judgment on Iraq is right. Now, it's time to heed that judgment so that we can successfully end the war while refocusing on the fight in Afghanistan. Sen. Obama has said repeatedly that there have been significant gains in lowering the levels of violence in Iraq. These gains have come from the heroic sacrifices of our men and women in uniform, as well as the success of the Sunni tribes in fighting al-Qaeda, and the cease-fire that has been respected by Shiite militias. But the stated purpose of the surge was to help bring about the political progress and economic development necessary for long-term stability in Iraq. That progress still lags. That is why we must welcome the growing consensus in both the USA and Iraq for a timeline that will allow the responsible redeployment of our combat brigades out of Iraq. I agree with Sen. Obama and the prime minister of Iraq that we can safely redeploy all our combat brigades out of Iraq in 2010, with a residual force to fight terrorists, train Iraqis and protect our personnel. This redeployment is absolutely necessary if we hope to restore our military strength and finish the fight against al-Qaeda and the Taliban in Afghanistan and Pakistan's tribal areas. This is the central front in the war on terror. This is where the 9/11 attacks were planned and where terrorists could be plotting against America today. With the Taliban and al-Qaeda on the rise and violence more severe than at any time since the beginning of the war, we must free up more resources in order to succeed. As Adm. Mike Mullen, the chairman of the Joint Chiefs of Staff, acknowledges, we can do so only if we redeploy our forces from Iraq. Success in Iraq must not be defined by staying in Iraq indefinitely; success is leaving Iraq to an Iraqi government that is reconciling its differences and taking responsibility for its future. It's time to encourage the Iraqi government to stand up on its own while we refocus on the war in Afghanistan and the broad range of national security challenges we face. Barack Obama is profoundly right that the next president must be more than commander in chief for Iraq -- he must meet challenges to America's security around the world. [Sen. Joe Biden, D-Del., is chairman of the Senate Foreign Relations Committee. He wrote on behalf of the Obama campaign.]