Contrary to the opinion held by the Trump administration, the massive withdrawal of the US troops from Afghanistan may not necessarily lead to the Taliban taking over all territories of the landlocked country. The country may also not be a safe spot for terrorists of all affiliations and other related malcontents as well.
Change in Taliban priorities
There are a number of reasons to assume such an outcome. The first and the most important reason is the Taliban itself. Although they control large swathes of the country, they are far from a dominating presence. The Afghan security forces have effectively kept them in check, with the Afghan special forces making a name for themselves in counter-insurgency operations. The US and the other western countries would also, doubtless, provide military firepower and funding to Kabul even after they move out. It is true that such a withdrawal would result in the Taliban occupying a few more tracts of land, but no more than that. The victory of the Taliban is not much likely in such a scenario.
The ground reality is much different. Public statements made by the Taliban show that they desire peace and reconstruction assistance. A Quranic justification is being offered for peace talks. It is clear that the organization has realized the futility of its wish to take Kabul, the Afghan capital by force. Pakistan, the main backer of the Taliban, has also become cautious when it came to the scenario of a Taliban-ruled Afghanistan.
Taliban and Islamic State
There is another factor at play here: the Taliban hates the Islamic State and vice-versa. The organization does not want the country to host any IS units. In fact, the Taliban killed more IS units than the Afghan security forces. Violent clashes are a regular occurrence between the two.
The Taliban's animosity towards the IS lies in its deep nationalistic outlook. It concentrates on nationalist objectives. The group has no international aims. Other than geopolitical differences, the strict interpretation of the IS when it comes to Sunni Islam has repelled the Taliban. The Wahhabi-Salafist traditions of IS have created tensions between the two groups. The leadership of the Taliban has instructed its cadre to kill IS members as a priority than hosting them in Afghan soil. It also helped that global terrorists have now other places to hole up in than Afghanistan. The Arab Spring has created a number of places in North Africa and the Middle East where they could operate in relative ease compared to Afghanistan, a land crisscrossed by the US drones.