WE have come to expect barbaric brutality from the most extreme of Islamist extremists, but yesterday's appalling massacre in Pakistan sinks to unplumbed depths.

There can be no ideological justification for targetting schoolchildren. The school in Peshawar seems to have been chosen because of its military connections, but it is utterly wrong for the extremists to take revenge on the parents by attacking the children – children have no responsibility for the political and military decisions of their parents.

The siege in Australia was different. Extremist ideology seems to have allowed the gunman, Man Haron Monis, room to plan abhorrent actions, but it is clear that he was a man with mental and sexual issues – as his own barrister said, he was a "damaged goods individual". The questions in Sydney – where the two hostages who died appear to have summoned superhuman bravery in an attempt to save their fellows – are likely to be as much about police tactics and surveillance as they are about the gunman's warped religious beliefs.

However, in Pakistan, the gunmen's beliefs are so warped that they may cause a strong group to unite against them. In recent months, the Pakistani government has launched a strong offensive in the lawless tribal lands against Taliban fighters. Many tribal leaders have been unsupportive but even they may now see that the extremists are so far beyond the pale that they will no longer oppose efforts to crush them.

So in the long term, some positive may emerge from those unplumbed depths. In the meantime, the words of Malala Yousafzai – the 17-year-old shot by the Taliban for daring to be a girl who wanted an education – are perfect. She said yesterday: “I am heartbroken by this senseless and cold blooded act of terror... Innocent children in their school have no place in horror such as this. I, along with millions of others around the world, mourn these children, my brothers and sisters – but we will never be defeated.”

There can be fewer with a stronger claim to the title of "person of the year" than Malala.