The Taliban

http://www.cfr.org/terrorist-organizations-and-networks/taliban/p35985#!/

The Taliban was toppled in Afghanistan in 2001 for harboring al-Qaeda, but it has not been defeated. With an estimated core of up to sixty thousand fighters, the Taliban remains the most vigorous insurgent group in Afghanistan and holds sway over civilians near its strongholds in the country’s south and east. It has also metastasized in neighboring Pakistan, where thousands of fighters in the country’s western tribal areas wage war against the government. Now, as the international combat mission in Afghanistan closes, the Taliban threatens to destabilize the region, harbor terrorist groups with global ambitions, and set back human rights and economic development in the areas where it prevails.

Though the Taliban appears unlikely to dismantle the Afghan government and revive its emirate, it poses the most serious challenge to Kabul’s authority even as the United States winds down the longest war in its history and NATO scales back its largest-ever deployment outside of Europe. The insurgents’ resilience calls into question a state-building project that has cost its international backers hundreds of billions of dollars.