There are roughly 100,000 American and North Atlantic Treaty Organization troops in Afghanistan.
NATO has been operating in Afghanistan since 2003. The alliance has more than 60,000 troops as part of a United Nations mandated contingent known as the "International Security Assistance Force" - or ISAF.
Analysts say NATO has three objectives in Afghanistan. The first is to assist the Afghan government in its efforts to rebuild and stabilize the country. The second is to train the Afghan army and police. And the third is to hunt down and eliminate insurgents in southern Afghanistan - home of the Taliban, ousted from power by a U.S.-led coalition in 2001.
The United States is the largest contributor to ISAF with approximately 30,000 troops. An additional 32,000 soldiers and Marines are part of the U.S.-led "Operation Enduring Freedom."
Tomas Valasek is a NATO and Afghan expert with the London-based Center for European Reform.
"The missions of '[Operation] Enduring Freedom' and forces under NATO's operation are really converging, gradually, over time. But the basic division is - if one can be drawn - is that '[Operation] Enduring Freedom' focuses on chasing down Osama bin Laden and the most active leaders of Al-Qaeda and the Taliban in Afghanistan, whereas the NATO forces are peacekeepers whose job is to help establish control by the Afghan national government," he said. "Of course the tasks have converged simply because the peacekeeping job the NATO forces are doing in Afghanistan has turned out to be a little bit more difficult than initially thought. And peacekeepers have really turned into combat troops," Valasek added.
This past July was the deadliest month ever for U.S. and NATO forces in Afghanistan - 76 coalition troops were killed, 45 of them American.
Analysts say in the run-up to the August 20 presidential elections, the Taliban has stepped up its attacks. They say the main fighting is still centered in the south, but the Taliban has expanded its range of action to the east and to the relatively peaceful north.
Sean Kay, with Ohio Wesleyan University in Delaware, Ohio, says over the past few years, the Taliban has changed some of its methods.
"The Taliban have adopted tactics that came out of Iraq - the suicide bombings that used to never happen in Afghanistan have been happening much more regularly, the improvised explosive devices on the ground - a very serious threat to our men and women taking risks for the country on the ground," he said.
Michael Williams with the University of London, says the Taliban is using classic hit and run maneuvers.
"The Taliban certainly feel that they have the advantage at the moment - it's dubious to say whether they do or not. They don't really control a lot of territory. What they do is they harass and harry. And so the NATO forces have to actually take, clear out territory and hold that territory," said Williams. "The Taliban just has to go in and out and punch holes and create chaos, which makes it an incredibly more easy task for them and makes it more difficult for the alliance," he said.
In addition, says Charles Kupchan with the Council on Foreign Relations (in Washington), counter-insurgency warfare has always been difficult, because insurgents often run away from the forces that are coming after them.
"In the case of Afghanistan, they can disappear across the border into Pakistan. And even though the United States is conducting attacks on Pakistan territory through drones [a pilotless aircraft operated by remote control], the United States does not have permission, if you will, to send its own forces into Pakistan territory," said Kupchan. "And so in that sense, the Taliban, to some extent, has safe harbor, can come across the border into Afghanistan, do damage and then sneak back into Pakistan," he said.
Many experts say NATO's credibility is at stake if it does not defeat the Taliban and help bring stability to the country.
Michael Williams of the University of London, describes what a successful Afghanistan might look like.
"Success in Afghanistan for the United States and its allies is a country that is broadly stable, with a centralized government that has the loyalty of regional factions of the country that are highly autonomous, that are providing generally for their own security and ensuring that no terrorist organization can find a safe haven in the country," said Williams.
Williams and others say such an Afghanistan can only come about if the international community provides the necessary economic, financial and reconstruction aid to help the Afghan government. They say NATO alone cannot stabilize the situation in Afghanistan.