The US invasion in 2001, the first phase has been very successful. And not because Americans have a weird military capabilities.
Taliban leader Mohammad Omar at that time then took the right decision not to fight the war machine of the West head-on, putting his supporters in the grave thousands, and retreat to dissolve. So the first few months since the Americans are actively attacked, in fact, they fought with emptiness. Occupants supported the "Northern Alliance". Total in this war, dubbed the operation "Enduring Freedom", from 2001 to 2014 attended the military 48 countries. West acted the same way as at the time of the USSR. In Kabul, it was planted puppet government set up power structures (of which separate conversation). But in 2002, Americans have felt the hard way that the Taliban have moved from a lull in guerrilla warfare against them. West increased its strength. In 2011, in Afghanistan there were around 133 thousand. Coalition troops only arrived from the United States of 90 thousand. But the result was the same as that of the shuravi. The government and the coalition forces controlled only the major cities and in some measure northeastern territory. Most of the country was under the rule of the Mujahideen. Afghan troops and police training and arming of the West are engaged in military, soon disappointed their backers. Not only the low combat capability, but mainly to the fact that they flourished desertion. Moreover, Afghan soldiers and police often open fire on troops from coalition forces. By 1 January 2015 the operation "Enduring Freedom" was terminated. But under the new operation "strong support" in Afghanistan, there are about 12.5 thousand. NATO military. Of these, more than 9 thousand. - Americans, about 1 thousand. - The Germans, and even minor contingents from 10 countries.
Beginning in the late summer of this year, the military activities of the Taliban are successful not only in the south and south-west, but in the northern non-Pashtun areas of the country where they previously rebuffed "Northern Alliance". In connection with the seizure of Kunduz was spread a message Akhtar Mansoor, where Taliban leader urged the people of Afghanistan to rally and help the mujahideen to expel the invaders, he also appealed to the authorities and said that there will be no retaliation against them if they move to it side. Despite the fact that the Taliban have declared a terrorist organization, we should not forget that their aim is an independent Afghanistan, it is not they but the "Islamic State" (against whom the Taliban are fighting) has plans for expansion in the countries of Central Asia and later in Russia.