House Minority Leader John Boehner has accused President Barack Obama of endangering the mission in Afghanistan by “delaying action” on sending more troops. But present policy would require more troops than America could ever send — as many as 650,000 troops for the next 12 to 14 years, according to the US Army and Marine Corps Counterinsurgency Field Manual metrics. This commitment of time and resources cannot be accomplished at a cost acceptable to Americans.

Many critics of the war, including Boehner, are not asking the right question when it comes to the eight-year campaign in Afghanistan: not whether the war is winnable, but whether the mission constitutes a vital national security interest. From that perspective the current open-ended strategy fails.

In his battlefield assessment of the war, General Stanley McChrystal, America’s top commander in Afghanistan, says without more troops the mission “will likely result in failure.” But success in Afghanistan would hardly be guaranteed even if Obama were to commit several hundred thousand troops and decades of armed nation-building.

It is well past time for the US to adapt means and ends. Rather than an indefinite military mission with large numbers of US troops, US strategy should focus on assisting and training Afghan forces in order to limit that country’s future dependence on foreign troops for security.

Growing and improving the effectiveness of the Afghan National Security Forces (ANSF) is limited and feasible. A focused mission of training the ANSF means America must support, rather than supplant, indigenous security efforts. In March, Obama committed 4,000 US trainers to Afghanistan, while NATO pledged an additional 5,000 military trainers and police. At that time, the Afghan National Army (ANA) had about 82,000 soldiers, a number scheduled to grow to 134,000 by the end of 2011. The Afghan National Police (ANP) stands between 85,000 and 90,000. It currently covers 365 districts, 46 city police precincts and has a presence in all 34 provinces.

But numbers tell only part of the story.

The Focused District Development program (FDD) is a district-by-district training regimen for police units. The FDD is directed by the combined security transition command Afghanistan, a joint service organisation under the command and control of US Central Command that is responsible for equipping and training Afghan security forces. Since it began in October 2007, a mere 52 of 365 police districts have successfully completed the program, despite training camps operating at maximum capacity.

The concept of proper police procedures and respect for the rights of citizens remains underdeveloped. “The first time they heard that they weren’t supposed to beat people, and they weren’t supposed to take their money, [but] that they were supposed to enforce laws and that their job was to protect the people, most police were surprised,” said Army Colonel Michael McMahon, the FDD’s director.

According to Karen Hall, police program manager in the Bureau of International Narcotics and Law Enforcement Affairs at the US Department of State, 75% of the Afghan national police are illiterate, which prevents many officers from filling out arrest reports, equipment and supply requests and arguing before a judge or prosecutor.

Going forward, training should be tied to clear metrics, such as whether Afghans can operate independent of coalition forces and can take the lead in operations against insurgents. As the war in Afghanistan rages on, Obama should be skeptical of any suggestions that the defeat of al-Qaida depends upon a massive troop presence.

Committing still more US personnel to Afghanistan undermines the already weak authority of Afghan leaders, interferes with the ability to deal with other security challenges and pulls the US deeper into a bloody and protracted guerilla war with no end in sight.