If ever mankind were going to agree about anything, the merit of eliminating the virus that causes polio would surely be high up the list. So the coordinated shooting of polio-immunisation volunteers in Pakistan is a bleak symbol of failure.
Poliovirus, one of humanity's oldest enemies, was among the most dangerous until the 1950s. The disease's other name, infantile paralysis, hints at the dread created by the epidemics of the last century.
There is no cure. Most victims are children, and most survive, but typically with twisted, paralysed limbs. So around the world, parents were joined in thanks in 1955 when a US scientist, Jonas Salk, unveiled a practical vaccine. Since then, immunisation work has moved so far and fast that there is now genuine hope of eradicating polio globally.
But for Pakistan, the murders of the past few days are pushing the country back into the previous century. Experts say the disease is still endemic in only three countries: Pakistan, Afghanistan and Nigeria. In all three, Islamist hardliners have denounced immunisation as a western trick, and have used deadly violence, such as this week's attacks, to prevent children from getting the vaccine. The credulous are told the vaccine causes the disease or makes people sterile.
But immunisation efforts have persisted, backed by the government in Islamabad and led by the World Health Organisation, and so the death toll in Pakistan is dropping, to only 56 last year. It is now possible to imagine a year in which immunisation workers die more often than polio victims. For now, the vaccination programme has been suspended, and yesterday the eighth polio worker was killed.
No one has claimed responsibility for the recent attacks, but there are obvious suspects. The Pakistani Taliban's suspicion and resentment of the immunisation effort increased when a local doctor, under cover of vaccination work, visited Osama bin Laden's Abbottabad compound before the US raid last year, apparently trying to get DNA proof of his identity.
This was an unwise intrusion of intelligence-gathering into a medical project that should transcend politics. But it is hardly a justification for the murder of volunteers trying to save children from a horrible disease - nor for the disdain for the children. Most new Pakistani cases are in tribal areas with little government presence.
The struggle against the Taliban and Al Qaeda is often presented as a contest between modernity and medievalism. That is an oversimplification - but one that the Taliban seems determined to reinforce. The victims of these latest attacks are not only the brave volunteers, of course. It is the Taliban's own children who will suffer because of these ignorant killings.