Kabul, Afghanistan ? The re-election of President Hamid Karzai creates new headaches for the Obama administration. But it also presents opportunities to be seized.

The August election was rigged; the dragged-out recount was a farce. A runoff scheduled for this Saturday was canceled after Karzai’s opponent withdrew, saying the process was too corrupt.

But Karzai’s victory by default offers the Obama administration an opening to do something it should have done months ago: devise a strategy to prevent Karzai from wrecking any chance of stabilizing Afghanistan.

Arriving in Kabul this week, I could see Afghans had wearied of the election process. The campaign posters of August were long gone, and few Afghans I spoke to planned to vote. The buzz in the dusty Afghan capital was not about presidential candidates, but rather the fear of swine flu, which has led many Afghans to wear face masks on the street.

Yet this tainted election has huge implications for Afghans and Americans. Whichever strategy President Obama finally adopts will require a competent government in Kabul. We have no such partner now.

U.S. military and civilian officials have prepared an alternative, bottom-up strategy that would focus on helping local and provincial officials. Such a strategy holds promise in a country with a history of weak central government. But Karzai can thwart it by appointing corrupt officials to provincial and local positions.

A prime example: Kandahar province, the birthplace of the Taliban, where U.S. troops are trying to roll back a resurgence of militants. They are being undercut by Karzai’s younger brother Ahmed Wali Karzai, the kingpin of the province, who has reputed links to the drug trade and control over appointments to key jobs.

President Karzai thumbed his nose at Obama’s call this week for “a new chapter” in the fight against corruption, saying he would launch an anticorruption campaign but wouldn’t fire key officials. He did say he would strengthen a weak anticorruption commission, something Obama is demanding. But what use is a commission when Karzai won’t clean his own house?

The Obama team has yet to develop a coherent Karzai strategy. Obama has distanced himself from Karzai. Vice President Joe Biden has tried scolding him. The special U.S. representative to the region, Richard Holbrooke, is said to be barely on speaking terms with him. Sen. John Kerry got some traction after hours of private talks with him.

Clearly, the administration isn’t closely enough attuned to Karzai’s modus operandi: Holbrooke failed to notice clear signs before the election that massive ballot-rigging was likely, according to election experts in Kabul.

When Karzai errs, Afghans often blame the foreigners who back him. “People see the international community and the government as two sides of the same coin,” said Shahmahmood Miakhel, chief of party for the U.S. Institute of Peace’s Kabul office, which deals with rule-of-law issues.

How, then, to persuade or pressure Karzai to change policies that undermine both countries? Here are some suggestions I’ve heard from senior U.S. military officials, U.S. civilian advisers, and knowledgeable Afghans:

President Obama must personally convince Karzai that we are serious about corruption. That will take a clear message delivered in private, perhaps during a walk in the woods at Camp David: The American public and Congress will not support the investment of more money and men to stabilize Afghanistan unless you are ready to clean up your act. Think of your legacy. I have to think of mine.

The administration must speak with one voice. The CIA reportedly pays Ahmed Wali Karzai for some services. Cancel the contract. “You cannot do anticorruption if Ahmed Wali is on your payroll,” said one U.S. adviser in Kabul. “Karzai watches our actions, not our words.”

Insist that any new development funding for Afghanistan be subject to fiduciary oversight, possibly by a distinguished international panel.

Some heads must roll among corrupt Karzai allies as a prelude to a new system of appointing cabinet and provincial officials. If Ahmed Wali Karzai remains in power in Kandahar, we’ll know nothing is changing.

After an election that displayed all of Karzai’s flaws, we must use the leverage that billions in aid should give us. Otherwise, we’re pouring money down the drain.