By Ian Bremmer

As President Obama works toward finalizing a new plan for Afghanistan, here are five reasons why the challenges U.S. forces face in building stability there are more formidable than those in Iraq:

1) Political legitimacy. Parliamentary elections in Iraq scheduled for January will spark violence, the results will create controversy, and the eventual leaders will take their places within a system that pits lawmakers and cabinet ministers against one another in a more-or-less direct struggle for power. But voters will turn out in large numbers, and Iraq's new political institutions are slowly developing a broad popular legitimacy. That's not true in Afghanistan, which might have been better off without elections earlier this year. Virtually no one believes President Hamid Karzai won the August vote; few will embrace him when he claims victory following the November 7 run-off. He may hold the office, but he has virtually no natural political base in the country. Karzai is not exactly a reliable partner in efforts to build lasting stability.

2) Training of local forces. U.S. forces have had real success in helping the Iraqi government build its police and security forces. The large-scale drawdown of U.S. troops beginning next year will create a power vacuum that encourages battles over political turf and control of oil revenues. We've seen an uptick in violence in recent weeks, and we'll see more in months to come. Corruption remains a serious problem. But the Iraqi government has shown considerable progress over the past year in asserting control over territory and in beating back challenges from insurgents. In Afghanistan, there's almost no local support for a national professionalized military. Because Karzai's government has so little legitimacy, and few local leaders believe he can offer protection against Taliban attacks, very few people are lining up to don a uniform and pick up a rifle.

3) International coordination. In the battle against insurgents in Iraq, the United States has called most of the shots -- with significant (though now more modest) help from Great Britain. American and British forces have been well coordinated from the start, both operationally and strategically. Afghanistan's International Security Assistance Force has included troops from 43 countries with widely varying degrees of professionalism, morale and operational capability. Short of the U.S. military accepting responsibility for the entire mission, there's no short-term fix here.

4) Tribal/warlord patronage networks. More than any other factor, the willingness of Sunni tribal leaders to partner with U.S. forces against a common external enemy has been central to improvements in Iraq's security over the past two and a half years. In Afghanistan, tribal leaders and local warlords face US requests for help against a domestic foe, the Taliban, with whom they may find themselves negotiating long after NATO forces have left the country.

5) Resource base. Iraq has enormously underdeveloped oil reserves, a relatively well-educated urban elite, a population with some limited but real sense of national identity, and a favorable geographical position for development of trade and investment ties with other countries in the region and beyond. For the foreseeable future, the bulk of Afghanistan's cash will come from foreign aid and opium production. Neither offers much hope as a source of long-term stability.

Iraq's government has a long way to go before it can function as a set of independent, secure and self-confident institutions and as guarantor of Iraq's long-term stability. But in Afghanistan, it will be years before local leaders can move from coping with serious problems to solving them. 

Ian Bremmer is president of Eurasia Group.

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