That Pakistan is a nation bound upon a wheel of fire is not in any doubt. The assassination of Salmaan Taseer, killed for speaking out against a blasphemy law that has been used time and again to persecute minorities and settle private scores, would itself have been a significant blow, depriving the nation of one of the few politicians willing to be fearless in facing down radicalism. But it was the image of lawyers sprinkling rose petals on to Taseer's smiling assassin – as though he were a bride and they the family of the groom welcoming him into their fold – that dealt a body blow from which Pakistan's liberals and progressives are unsure they can ever recover.

How far the nation has travelled over the decades is evident in the distance between the petal-throwing lawyers and the finest document in the country's history – not its ever-amending constitution, but a judicial report penned by Justices Munir and Kayani in 1954, in response to the anti-Ahmadiyya riots of 1953, which marked the first time the religious right used violence against the state to try and push forward its programme of defining Pakistan.

The riots were designed to press the government into declaring members of the Ahmadiyya sect as non-Muslim. The attempt failed, but showed up certain dangerous problems within the new state. The Munir-Kayani report didn't merely look at the facts surrounding the riots, but delved into theology, philosophy and dry wit to expose the dangers and absurdity of the religious right's position. In a particularly brilliant section the report asks 10 ulema (Islamic scholars) to lay out the minimum conditions a person must satisfy to call themselves a Muslim. After reproducing the wildly divergent answers, the justices write: "Need we make any comment except that no two learned divines are agreed on this fundamental ... And if we adopt the definition given by any one of the ulema, we remain Muslims according to the view of that alim [scholar] but kafirs [infidels] according to the definition of everyone else."

One thing the justices never envisioned as they highlighted the impossibility of "an Islamic state" when so many different versions of Islam exist, was that anything could band together the disparate groups of the religious right. Yet that is precisely what happened around demands for the blasphemy laws to be amended. There are far too many differences and enmities between those groups for agreement to stretch very far. But the site of agreement has encroached on the liberal space within Pakistan.

The extent of this encroachment became clear recently as many of those who had been insisting that a decisive response was needed in the name of anti-extremism blogged and tweeted their delight at a fatwa apparently issued by a previously unheard-of mufti, Muhammad Idris Usmani of the Jamia Islamia. He declared that, on examining all the evidence, it was clear Salmaan Taseer was not guilty of blasphemy; rather, the real blasphemers were those who praised or justified his assassination in the name of Islam. Their punishment, in accordance with the Qur'an, was "execution, or crucifixion or the cutting off of hands and feet from opposite sides, or exile". He then went on to list all those real blasphemers, including "200 lawyers who cheered up the killer; dozens of journalists, scholars and media persons who justified the killing".

The authenticity of the fatwa – and the man himself – is in serious doubt. But the responses to it from liberals were genuine enough. Some who expressed delight at the fatwa probably would be entirely pleased to see the execution of those cheering on the assassin – in Pakistan you can be both a liberal and a fascist, so long as you're a secular fascist. But in other places the approval for the mufti seems indicative of a deep despair born of a certainty that extremism has won. We are left with the image of liberalism's last act – the attempt to hurl extremism's weapons back at it, not in the hope of causing serious damage but because there are no other weapons left. At least, that's how it feels today. That is the cheeriest note it's possible to strike at the moment.

For those who insist that Pakistan's religious right problem started with the rule of General Zia in 1977, look at the warning within the Munir-Kayani report of 1954: "Provided you can persuade the masses to believe that something they are asked to do is religiously right or enjoined by religion, you can set them to any course of action, regardless of all considerations of discipline, loyalty, decency, morality or civic sense."

That should have been a wake-up call; it wasn't. Two decades later, Zulfikar Ali Bhutto, who had campaigned on a secular socialist platform, declared the Ahmadiyyas non-Muslim, in an awful attempt to outflank the religious right. Like many other politicians before and since, he thought he could use Islamic rhetoric to his advantage, without too much concern about fallout. And so we are left with the haunting final words of the report: "But if democracy means the subordination of law and order to political ends – then Allah knoweth best and we end the report."