It was a bloody reminder that the dark days of extremist violence appeared to have returned to Pakistan: a suicide attack on a religious festival in the country’s southwest this past week that left around 60 people dead. For nearly a decade, Pakistan had seemingly broken the cycle of such deadly attacks. In 2014, the country’s security forces carried out a large-scale military operation in the tribal areas near Afghanistan, forcing militants across the border and returning a relative peace to the restive frontier region.

But since the Taliban seized power in neighboring Afghanistan in August 2021, offering some groups safe haven on Afghan soil and starting a crackdown on others that pushed their fighters into neighboring Pakistan, the violence has roared back. The number of terrorist attacks in Pakistan rose by around 50 percent during the Taliban’s first year in power, compared with the year before, according to the Pak Institute for Peace Studies, which monitors extremist violence and is based in Islamabad, the capital of Pakistan.

This year, the pace of attacks has continued to rise. The attacks themselves have also become bolder, reviving the fears of a terrorism-scarred nation. In January, a suicide bombing at a heavily guarded mosque killed more than 100 people. A month later, militants struck the heart of Pakistan’s largest city, Karachi, waging an hours-long siege at the police headquarters. Another suicide blast, at a political rally, killed more than 50 people in July. The violence has stoked fears that the region — already home to one of the highest concentrations in the world of groups in the U.S. Foreign Terrorist Organizations list — is becoming a hotbed of international terrorism. It has also fuelled growing tensions between the Pakistani government and Taliban officials, who deny offering shelter to militant groups, including their ally, the Pakistani Taliban, also known as Tehrik-i-Taliban Pakistan, or T.T.P.

So far, there is little evidence of significant action by the Pakistani military to stamp out the militants. Pakistan can no longer count on the American military support that helped it drive out the militants a decade ago, and many believe that the country — already grappling with entrenched political and economic crises — is largely powerless to stop the violence.

Pakistani government’s military efforts are hindered “mainly because of political divisions and financial constraints,” said Adam Weinstein, deputy director of the Middle East program at the Quincy Institute, a Washington-based think tank. “It’s doubtful whether they could sustain a full-fledged campaign against the T.T.P.,” he added.

The Pakistani Taliban, an ideological twin of the Taliban in Afghanistan, seeks to impose strict Islamist rule in Pakistan’s border areas and has been behind most of the attacks over the past two years. Founded in 2007, the group controlled swaths of the tribal areas along the border until the military crackdown in 2014.

With the Taliban back in power in Afghanistan, the group has resurged. Hundreds of Pakistani Taliban fighters were freed from Afghan prisons during the takeover. They armed themselves with American military equipment once provided to the U.S.-backed Afghan government, according to the Pakistani authorities. The group’s current leader, Mufti Noor Wali Mehsud, has also intensified efforts to bolster the group’s ranks, successfully luring outfits affiliated with Al Qaeda, as well as fighters from anti-Shia groups and several Pakistani militants who were part of the Taliban insurgency in Afghanistan.