Wes Hickman (202) 224-5972 or Kevin Bishop (864) 250-1417

When Gen. David Petraeus testifies before Congress tomorrow, he will step into an American political landscape dramatically different from the one he faced when he last spoke on Capitol Hill seven months ago.

This time Gen. Petraeus returns to Washington having led one of the most remarkably successful military operations in American history. His antiwar critics, meanwhile, face a crisis of credibility – having confidently predicted the failure of the surge, and been proven decidedly wrong.

As late as last September, advocates of retreat insisted that the surge would fail to bring about any meaningful reduction in violence in Iraq . MoveOn.org accused Gen. Petraeus of "cooking the books," while others claimed that his testimony, offering evidence of early progress, required "the willing suspension of disbelief."

Gen. Petraeus will be the first to acknowledge that the gains in Iraq have come at a heavy price in blood and treasure. We mourn the loss and pain of the civilians and service members who have been killed and wounded in Iraq , but adamantly believe these losses have served a noble cause.

No one can deny the dramatic improvements in security in Iraq achieved by Gen. Petraeus, the brave troops under his command, and the Iraqi Security Forces. From June 2007 through February 2008, deaths from ethno-sectarian violence in Baghdad have fallen approximately 90%. American casualties have also fallen sharply, down by 70%.

Al Qaeda in Iraq has been swept from its former strongholds in Anbar province and Baghdad . The liberation of these areas was made possible by the surge, which empowered Iraqi Muslims to reject the Islamist extremists who had previously terrorized them into submission. Any time Muslims take up arms against Osama bin Laden, his agents and sympathizers, the world is a safer place.

In the past seven months, the other main argument offered by critics of the Petraeus strategy has also begun to collapse: namely, the alleged lack of Iraqi political progress.

Antiwar forces last September latched onto the Iraqi government's failure to pass "benchmark" legislation, relentlessly hammering Prime Minister Nouri al-Maliki as hopelessly sectarian and unwilling to confront Iranian-backed Shiite militias. Here as well, however, the critics in Washington have been proven wrong.

In recent months, the Iraqi government, encouraged by our Ambassador in Iraq , Ryan Crocker, has passed benchmark legislation on such politically difficult issues as de-Baathification, amnesty, the budget and provincial elections. After boycotting the last round of elections, Sunnis now stand ready to vote by the millions in the provincial elections this autumn. The Iraqi economy is growing at a brisk 7% and inflation is down dramatically.

And, in launching the recent offensive in Basra , Mr. Maliki has demonstrated that he has the political will to take on the Shiite militias and criminal gangs, which he recently condemned as "worse than al Qaeda."

Of course, while the gains we have achieved in Iraq are meaningful and undeniable, so are the challenges ahead. Iraqi Security Forces have grown in number and shown significant improvement, but the Basra operation showed they still have a way to go. Al Qaeda has been badly weakened by the surge, but it still retains a significant foothold in the northern city of Mosul , where Iraqi and coalition forces are involved in a campaign to destroy it.

Most importantly, Iran also continues to wage a vicious and escalating proxy war against the Iraqi government and the U.S. military. The Iranians have American blood on their hands. They are responsible, through the extremist agents they have trained and equipped, for the deaths of hundreds of our men and women in uniform. Increasingly, our fight in Iraq cannot be separated from our larger struggle to prevent the emergence of an Iranian-dominated Middle East .

These continuing threats from Iran and al Qaeda underscore why we believe that decisions about the next steps in Iraq should be determined by the recommendations of Gen. Petraeus, based on conditions on the ground.

It is also why it is imperative to be cautious about the speed and scope of any troop withdrawals in the months ahead, rather than imposing a political timeline for troop withdrawal against the recommendation of our military.

Unable to make the case that the surge has failed, antiwar forces have adopted a new set of talking points, emphasizing the "costs" of our involvement in Iraq , hoping to exploit Americans' current economic anxieties.

Today's antiwar politicians have effectively turned John F. Kennedy's inaugural address on its head, urging Americans to refuse to pay any price, or bear any burden, to assure the survival of liberty. This is wrong. The fact is that America 's prosperity at home and security abroad are bound together. We will not fare well in a world in which al Qaeda and Iran can claim that they have defeated us in Iraq and are ascendant.

There is no question the war in Iraq – like the Cold War, World War II and every other conflict we have fought in our history – costs money. But as great as the costs of this struggle have been, so too are the dividends to our national security from a successful outcome, with a functioning, representative Iraqi government and a stabilized Middle East . The costs of abandoning Iraq to our enemies, conversely, would be enormous, not only in dollars, but in human lives and in the security and freedom of our nation.

Indeed, had we followed the path proposed by antiwar groups and retreated in defeat, the war would have been lost, emboldening and empowering violent jihadists for generations to come.

The success we are now achieving also has consequences far beyond Iraq 's borders in the larger, global struggle against Islamist extremism. Thanks to the surge, Iraq today is looking increasingly like Osama bin Laden's worst nightmare: an Arab country, in the heart of the Middle East , in which hundreds of thousands of Muslims – both Sunni and Shiite – are rising up and fighting, shoulder to shoulder with American soldiers, against al Qaeda and its hateful ideology.

It is unfortunate that so many opponents of the surge still refuse to acknowledge the gains we have achieved in Iraq . When Gen. Petraeus testifies this week, however, the American people will have a clear choice as we weigh the future of our fight there: between the general who is leading us to victory, and the critics who spent the past year predicting defeat.

The following oped by Senators Lindsey Graham and Joe Lieberman first appeared in the Wall Street Journal on April 7, 2008.