HIS bargaining chip was the lives of children. In June, Hafiz Gul Bahadur, a government-backed warlord in the lawless Pakistan province of North Waziristan, issued his ultimatum: until American drone attacks on the territory he controls stop, there will be no polio vaccinations.
The unilateral decision, made by the old men of the High Council of Mujahideen and announced by Bahadur, declared the villages of his dominion were willing to chance a polio outbreak in an effort to force America's hand.
"As long as drone strikes are not stopped in Waziristan there will be a ban on administering polio jabs," a statement from the council said.
Drones are feared, and deeply resented in the north-west of Pakistan. Forty-four attacks have killed 333 people this year. But the US will not cease the drone strikes it says are precision attacks on terrorists who wage war in Afghanistan before retreating to Pakistani mountain hideouts.
Bahadur's desperate demand knowingly put a quarter of a million children at risk of a disease that kills or disables for life, and which, once caught, has no cure. The drones, he argued, are worse: "Polio infects one child in a million [sic], but hundreds of Waziri women, children and elders have been killed in drone strikes."
His ultimatum came, too, with the threat of violence. If polio vaccinators came to villages he controlled, "no one will have the right to complain about . . . any violation".
But for all the brinkmanship, the demands and dares haven't helped the children of North Waziristan.
For the moment, they live with both. The dual threats of a drone strike and a polio outbreak remain very real.
The global effort to eradicate polio, spectacularly successful across so many countries, is now focusing its efforts on the final three nations from where the disease has never been wiped out, and where vaccination efforts are most difficult: Nigeria, Afghanistan, and Pakistan.
And for the moment, it is meeting its fiercest opposition in Pakistan, where a public health issue has been conflated with geopolitical disputes, the spillover from a war in Afghanistan, and virulent anti-American sentiment, to the harm of those who live there.
Pakistan's long-running, but low-level, resistance towards the UN-run polio vaccination program erupted into unprecedented violence this week, with the slaying of eight polio workers in three days, during a nationwide immunisation drive. A ninth health worker died on Thursday in hospital from injuries sustained in one of the attacks.
Six of those killed were women. The youngest was 17.
The murders were in Peshawar, the capital of north-western Khyber Paktunkhwa province, and in Pakistan's largest city Karachi, in the south. In most cases, polio workers on the streets were gunned down by men riding on motorcycles, in what appear to be planned, and carefully co-ordinated, attacks.
In response, the UN has suspended its polio program, and pulled its workers out of dangerous areas.
"Those killed or injured, many of whom are women, are among hundreds of thousands of heroes who work selflessly to eradicate polio," the World Health Organisation and UNICEF said in a joint statement. "Such attacks deprive Pakistani's most vulnerable populations - especially children - of basic, life-saving health interventions."
The Pakistani Taliban has denied responsibility, but the network has previously declared the polio eradication program "haram" (forbidden), and the co-ordinated nature of the attacks has meant suspicion has fallen on its members.
Without naming the organisation, police deputy inspector Shahid Hayat blamed "the militants who have issued a fatwa against polio vaccination in the past" for the killings.
(It's been supposed the Taliban's uncharacteristic silence may be out of a desire to avoid the sort of public backlash that followed its shooting of 15-year-old girls' education campaigner Malala Yousafzai in October.)
But the attacks this week strike at the very heart of the polio eradication effort. Polio is transmitted person-to-person, through faeces, so usually infects children living in unsanitary conditions, typically slum neighbourhoods without toilets.
Polio can paralyse or kill within hours of infection. Once caught, there is no cure. But eradicating the disease is not a complex, high-tech endeavour.
The Sabin vaccine, developed half a century ago, is a pink liquid. Children aged under five receive two drops orally, ideally at least four times (in countries like Pakistan where birth certificates are rare, children are asked to reach over their head with their right arm to touch their left ear. If they can reach they are old enough not to require the vaccine).
But immunising a country's population is a mass effort, requiring mass compliance to be effective. Pakistan wants to reach 33 million children this year. This requires an army of volunteers to go door to door to every house in every neighbourhood across the country during nationwide drives to vaccinate every child.
The attacks this week demonstrate that those volunteers, the most visible and vital components of the polio immunisation program, are also its most vulnerable.
The volunteers don't wear uniforms, but they are clearly identifiable. They walk, door-to-door, in teams of three or four, wearing name-tags, and carrying clipboards and small styrofoam containers containing vials of vaccine. It is undoubted that they were specifically targeted this week.
In the Peshawar attack, men on motorbikes stalked two sisters as they walked from house to house. Once the sisters entered a quiet street, the gunmen opened fire. One of the sisters, Farzana, was killed instantly, the other was uninjured.
The volunteers mark the door jamb of every house visited with chalk hieroglyphs that tell subsequent vaccinators the number of children who live there, and the date of the last vaccination.
One team can immunise up 200 children a day. For their work, volunteers are paid a little over $2.50 a day.
The majority of polio vaccine volunteers are women: they are more readily granted access into the inner rooms of homes, and mothers are more willing to hand over infants and children to another woman.
International agencies run Pakistan's polio program, but the country's government says it is committed to the cause.
President Asif Ali Zardari claims the polio eradication campaign as a "personal mission", while Prime Minister Raja Pervez Ashraf said in the wake of this week's attacks "we cannot and would not allow polio to wreak havoc on the lives of our children".
Earlier this year, the government said it would fine the parents of non-immunised children, and also appealed to clerics in Saudi Arabia, asking them to issue fatwas to counter Taliban decrees against vaccinations.
There has been success. In 1994, there were 20,000 cases of polio in Pakistan. Last year, it was 198 and this year, just 56. But among swaths of the Pakistani population there remains a deep mistrust of the polio program, seen in parts of the country as an American conspiracy.
In the places vaccinators can reach, only about 1 per cent of homes refuse the vaccination. But in pockets where resistance exists, widespread and long-standing attitudes have been stubbornly inimical to change.
Many clerics, particularly in the country's north, are openly hostile to the vaccinators, and have campaigned against immunisation, telling followers it is a Western plot to sterilise Muslim girls.
Mullah Nazir, an influential cleric in North Waziristan, described the vaccine as the "ethnic cleansing" of Muslims.
Suspicion of an ulterior motive has been strengthened by the case of the Pakistani doctor Shakil Afridi, whose bogus hepatitis B immunisation campaign helped the CIA track down Osama bin Laden.
Afridi used the immunisation campaign cover to obtain samples from bin Laden family members. Afridi's samples allowed the US to confirm that members of the al-Qaeda leader's family were hiding in a compound in Abbottabad, ahead of the raid by navy SEALs that killed the terrorist kingpin last May.
Afridi was subsequently sentenced to 33 years in jail, under Raj-era treason laws, by a tribal Pakistani court (in a move that has further strained US and Pakistan relations).
In banning polio vaccinators from the territory he controls, Hafiz Gul Bahadur cited the bin Laden case. "Polio campaigns are also used to spy for America against the Mujahideen, one example of which is Dr Shakil Afridi," he said.
A simple accident of geography has also helped frustrate the effort to wipe out polio from Pakistan. It is in the same poor, restive north-west border regions, where government control is weak and insurgent influence strong, that polio is still prevalent, and that drone strikes occur. That allows critics of foreign intervention in Pakistan to conflate the two issues, and in the case of Bahadur, use one as a bargaining chip against the other.
Sometimes, however, it is far more prosaic issues that halt the progress of the polio vaccination mission.
This year, a grand Jirga - council of elders - of four tribes in North Waziristan voted to boycott polio vaccinations until the Pakistan government provided electricity to their villages.
The Asa Khel, Dhur Dhanee, Muskee and Dosalee tribes outlawed polio vaccinators from entering their villages. "We have been without electricity for the last 30 years and the government is ignoring the problem," Dhur Dhanee elder Malik Mashal Khan said. "We will continue our boycott until the government fulfils our demand. Our children die of scorching heat and mosquito bites, what difference does it make if they die of polio?"