The Hindu Kush mountains in Afghanistan. NATO troops have been fighting in Afghanistan for seven years now. But progress has been slow and in recent years, the Islamist Taliban has enjoyed a resurgence.

US troops patrolling an area with reported Taliban presence in mid-February. The US would like to see greater troop commitments from its European allies.

US troops on patrol in the remote Shemgal Valley. US Secretary of Defense Robert Gates on Wednesday said “I think the likelihood of getting the allies to commit to significant numbers of additional troops is not very great.”

US troops calibrating an M198 Howitzer in Kala Gush, Afghanistan. US President Barack Obama has pledged to send an additional 17,000 troops to Afghanistan, consistent with his concern that the country represents the central front in the fight against terrorism.

French and US patrol vehicles in the Kapisa Province. According to a survey released in February, just over half of Afghans think that NATO’s presence is a part of the country’s security problem.

A US soldier destroying opium poppies. One of the greatest challenges facing NATO allies in Afghanistan is the drug trade, which helps finance Taliban activities.

The ruins of old Soviet tanks, remnants of the Soviet invasion of Afghanistan which ended in 1989 after a decade-long war. Many worry that Afghanistan could become NATO’s Vietnam.