The photos and reports of abuse at Abu Ghraib have understandably commanded America's attention. The soldiers who committed these atrocities have marred the reputation of our country and have made the lives of American personnel in Iraq more dangerous and difficult. Their crimes have led some observers to question our presence in Iraq and the justness of our cause.

Yet we will have exponentially magnified the mistakes made in Abu Ghraib if we allow these abuses to destroy our goal of a free and democratic Iraq. Success in Iraq remains possible, and it is more necessary now than ever. While the path to success must involve a number of steps, a few are absolutely critical. We have a security problem and a political problem, and we need solutions for both.

On the security side, we must begin with an immediate and significant increase in our troop levels. We should sharply increase the number of troops, including Marines and Special Operations forces, to conduct offensive operations, and add other types of forces, including linguists, intelligence officers and civil affairs officers. Relying solely on reservists, guardsmen, extended rotations and troops in the country to fill the security gap will not be sufficient. The Pentagon should strongly consider redeploying large numbers of troops from our bases in the United States, Europe, Japan and elsewhere. They are needed in the short to medium terms to stabilize key areas, turn the tide against the insurgents and return a sense of tangible authority to the country.

We will also continue to see instability increase as long as we make security pledges that are left unfilled. Our retreat from Fallujah has emboldened the insurgents and convinced some Iraqis that America lacks the will or the means to enforce its demands. While it is difficult to criticize tactical decisions from Washington, our personnel in Iraq must show the determination to keep their promises. Our troops can display full resolve only by exercising the military action necessary to back up the words of political authorities. Part of this determination must mean a quick end to all independent militias in Iraq. The country will never be stable as long as bands of armed fighters roam. The coalition authorities should fold into the new Iraqi army the vetted members of some militias, and the rest must face a choice: Disarm and disband or be forced to do so.

While we pursue a revamped security strategy, we also need to deal anew with the political situation in Iraq. With no one yet identified to lead Iraq after the transfer of sovereignty, and with some questioning even the date for the handover, there is a dangerous political vacuum. This has resulted in uncertainty and instability, and an increasing sense of "us versus them," in which the "them" is the coalition. We need to reduce the uncertainty as soon as possible by clearly announcing now our plan for events after June 30, beginning with a commitment to the turnover date. Were we to decide now that the United States will continue the occupation beyond June 30, we would feed the suspicions of all those who believe that we are in Iraq for conquest rather than liberation.

The June 30 handover must mean more than the transfer of policymaking power from Coalition Provisional Authority headquarters to the new U.S. Embassy. It must also mean something more than handing power -- whether over government ministries or military forces -- back to the Baathists from whom we rightly wrested it a year ago. The handover should represent a short-term transfer of sovereignty to a caretaker government that will quickly pave the way for elections. No Iraqi government can derive legitimacy simply through selection by the United Nations or the United States. Real legitimacy is derived only from the free choice of the Iraqi people.

For this reason, we should strongly consider moving up the date of the planned elections from January to this fall. Iraqis currently have little opportunity to turn their political desires into government decisions, and Shiite, Sunni and Kurdish Iraqis all fear losing out in a political process dominated by outsiders. In this atmosphere, some have turned to violence, and more may follow. The political focus in Iraq should revolve around waging and winning elections, not around currying favor with or opposing the United Nations and the United States. Accordingly, the United States and the United Nations should move ahead as quickly as possible with a full plan for democratic elections, one that will ensure that Iraqi liberals can compete fairly in local constituencies with Islamists organized nationally.

In Iraq our national security interests and our national values converge. Iraq is the test of a generation, for America and for our role in the world. We will endure setbacks, as the past weeks have painfully illustrated. But our focus must remain on our ultimate objective: helping to fashion a responsible and representative Iraqi government, with legitimacy in the eyes of Iraqis and the world. We do not have the luxury of time.

John McCain is a Republican senator from Arizona. Joe Lieberman is a Democratic senator from Connecticut.