The murder of nine polio vaccination workers during 48 hours in Pakistan has all the hallmarks of a Taliban operation: coordinated, ruthless and monstrous. The attacks have succeeded in shutting down an anti-polio campaign in Pakistan’s largest city, Karachi, and other areas.

This could hardly come at a worse time in the global effort against the disease. Polio was one of the most feared diagnoses of the 20th century. The virus attacks the brain and spinal cord, swiftly destroying the cells that control muscles. As late as the 1950s, 20,000 Americans were paralyzed each year. But since the development and distribution of the polio vaccine, America saw its last naturally occurring case in 1979.

Over the past few decades, this outcome has been nearly duplicated on a global scale. More than 99 percent of infections have been eliminated. The United Nations and U.S. health authorities, with support from private groups such as the Gates Foundation and Rotary International, are pursuing the remaining 1 percent of polio infections into remote areas of three countries: Nigeria, Afghanistan and Pakistan. A final, successful push could render the virus extinct in the wild, like smallpox before it. A failure could result in a quickly spreading outbreak. (The suspension of anti-polio efforts in northern Nigeria in 2002 and 2003 resulted in new cases in 16 countries.)

In Pakistan, more than 80,000 field workers are attempting to vaccinate 33 million children in a geographically rolling campaign. Teams of three to eight vaccinators go door to door in a focused area, providing drops to every child younger than 5. Others are posted at bus and train stations to cover children in transit. It is impossible to provide security to an effort of this size — which the Taliban has noticed.

The targeting of health workers is another reminder of Taliban tactics and ideology. It is a movement, in its various forms, recently responsible for shooting 15-year-old education activist Malala Yousafzai in the head and neck and beheading 17 men and women in the Musa Qala district of Afghanistan’s Helmand province. Vaccination has been a long-standing obsession. In June, a Taliban warlord declared, “Polio drops will be banned in North Waziristan” until U.S. drone strikes cease. It is a strategy both cruel and typical: the intentional infliction of paralysis on Pakistani children as a negotiating ploy.

Yet some blandly talk of negotiations with the Taliban in Afghanistan, even contemplating their return to power. It would be a nightmare of oppression, misogyny and revenge.

There is also, however, a complex issue here for Americans to consider. The Taliban and associated groups are exploiting a broad suspicion of vaccines in Pakistan, to which the U.S. war on terrorism has unintentionally contributed. Part of the effort to confirm Osama bin Laden’s location involved a fake CIA hepatitis vaccination program, designed to extract DNA samples from people living in his Abbottabad compound. The Taliban have used this revelation to raise suspicions about all vaccination programs being a cover for U.S. intelligence.

In retrospect, the CIA operation was a mistake. Exploiting the unique social standing of health workers in the preparation for a military raid was bound, if revealed, to undermine vaccination efforts. And such things are often revealed. The CIA does not appear to have adequately considered the downsides of, and alternatives to, this particular action. Health and development efforts in Pakistan — on which the United States spends billions each year — are also part of the fight against extremism.

But the effects of a single CIA operation should not be overestimated. The conspiratorial rumors about vaccines in some Muslim societies — that they are unclean under Islamic law, that they contain the AIDS virus, that they are designed to sterilize Muslim minority groups — existed before the bin Laden raid.

And even in an atmosphere of suspicion in Pakistan, parental refusal of the polio vaccine for their children is a relatively small part of the problem — accounting for less than 2 percent of the children approached in most of the country. “The bigger issue to tackle,” says Jay Wenger, director of the Gates Foundation’s polio program, “is the effectiveness and efficiency of the vaccine delivery program. . . . Improving its quality is still the biggest barrier.”

That delivery program is precisely what the Taliban is targeting in its recent escalation. And it would make use of any excuse. The Taliban sacks the world and history for grievances to justify murder. And now they intentionally paralyze children as a strategy of war.