The limited response set off fresh scrutiny of Pakistan’s military, a force with 500,000 soldiers and a similar number of reservists. The army receives $1 billion in American military aid each year but has repeatedly declined to confront the Taliban-led insurgency, even as it has bled out of Pakistan’s self-governed tribal areas into Pakistan proper in recent months.

The military remains fixated on training and deploying its soldiers to fight the country’s archenemy, India. It remains ill equipped for counterinsurgency, analysts say, and top officers are deeply reluctant to be pressed into action against insurgents who enjoy family, ethnic and religious ties with many Pakistanis.

In the limited engagements in which regular army troops have fought the Taliban in the tribal areas and sections of the Swat Valley, they not only failed to dislodge the Taliban, but also convinced many Pakistanis that their own military was as much of a menace as the Islamic radicals it sought to repel, residents and analysts say.

In Washington, a Defense Department official who is monitoring Pakistan closely said that the poorly trained constabulary force was sent Thursday because Pakistani Army troops were not available, and Pakistani generals were reluctant to pull reinforcements off the border with India  something American officials have encouraged them to do.

Image In Pakistans Buner district on Thursday, a barber looked at the Shave is forbidden warning that the Taliban wrote on the window of his shop. The Taliban now control the region. Credit... Tariq Mahmood/Agence France-Presse — Getty Images

“It illustrates there is a lack of political will in the Pakistan civilian leadership to confront these Pakistan Taliban,” said Senator Jack Reed, a Rhode Island Democrat on the Armed Services Committee who just returned from his fifth visit to Pakistan. “The Taliban sense this huge vacuum that they can pour into.”