Editor's note: David Cortright is director of policy studies at the University of Notre Dame's Kroc Institute for International Peace Studies and author of the recently released book "Ending Obama's War: Responsible Military Withdrawal From Afghanistan" (Paradigm Publishers, 2011).
(CNN) -- President Barack Obama's decision to begin military withdrawals from Afghanistan is welcome, but the scale of the withdrawal is insufficient.
The president announced that 33,000 troops will be coming home by the end of next summer, but he offered no change to the underlying military strategy. By keeping most U.S. troops in place beyond 2012, the president has guaranteed that the war will continue.
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U.S. troops will remain bogged down in an unwinnable counterinsurgency campaign. American taxpayers will remain on the hook for war-related expenses that are running at $10 billion a month. Kleptocrats in Kabul will continue to enrich themselves at our expense. Insurgents in the region will see their demands for the removal of foreign troops spurned and will likely fight on. Attempts at negotiation and peacemaking will languish.
It doesn't have to be this way. Instead of pursuing costly and uncertain military means, the United States could adopt a strategy that prioritizes political solutions.
An alternative approach would focus on negotiating a cease-fire and forging a political agreement between the Taliban and Hamid Karzai's government. It would support the deployment of a peacekeeping force under U.N. authority. It would pledge continued funding for social development and create a diplomatic compact among neighboring states to stabilize the region. None of this will be possible without a plan for the removal of U.S. troops. NATO has agreed to turn over security responsibilities to the Afghan government by 2014, but it has not pledged to remove all troops by that date.
U.S. and NATO leaders have assumed that greater military pressure will subdue the Taliban and reduce the level of violence, but some of the trends have been in the opposite direction. The increased involvement of U.S. and allied troops in recent years has been accompanied by growing insurgency and spreading Taliban influence.
According to the most recent U.N. report, civilian casualties in Afghanistan reached the highest level yet recorded last year.
The alternative strategy attempts to reverse this deadly dynamic. It seeks to remove the causes of the insurgency by withdrawing U.S. troops. It links demilitarization to a broader set of political and security agreements that would include preserving the Afghan Constitution and preventing the use of Afghan territory for terrorist operations.
Military disengagement is not without risks. If U.S. withdrawal creates a security vacuum, civil war could resume. This is why a peacekeeping force is necessary. Its mission would be to protect civilians and enforce cease-fire arrangements. Henry Kissinger has suggested the creation of an "enforcement mechanism" that could involve an international force. Others have recommended a protection force under U.N. auspices. Taliban leaders have proposed a "Muslim-led" security force and have vowed not to attack it.
Indonesian diplomats I interviewed recently have expressed interest in the idea of an interim security force. As the world's largest Muslim country, Indonesia could play an important role in creating such a force, but it will only do so under U.N. authority, as an alternative to rather than a continuation of the current U.S.-led military operation.
Steps are also needed to preserve the gains Afghan women have achieved over the past decade. This will require continued funding for proven development programs that expand schooling, health care and economic opportunities. It also means supporting the demands of women to be represented fully in Afghanistan's High Peace Council and in all negotiations about the country's political future.
For now, more peaceful options in Afghanistan have been deferred in favor of continued war. The president has pointed in the right direction by starting a drawdown, but the pace of withdrawal is too meager to make a difference in breaking the cycle of violence. Ending the war will require deeper reductions and a strategy that pursues political rather than military solutions.
The opinions expressed in this commentary are solely those of David Cortright.