Louis Theroux looks back on the accomplishments of Fred Phelps. Theroux knows more about the Phelps family than most people, because he did two BBC documentaries about them.

An eternity in hell is the fate of anyone who doesn’t get baptised into the WBC and travel the country waving hate-filled placards at political events, colleges and places associated – even in the most tortuously oblique way – with tolerance of homosexuality.

While I was with them, they had a regular local picket of a hardware store that sold Swedish vacuum cleaners. The Swedish government had imprisoned a pastor for homophobic preaching, and for the WBC that made the store a legitimate target for a ritualised Biblical smackdown. For the newcomer, these pickets were bizarre, not simply because of the venom of the signs, but also because they clashed with the banality of the family interaction. For the Phelpses, it was another day at the office – there was a water-cooler ambience of chit-chat. Meanwhile, everyone, even the youngest child, was carrying placards saying: “Thank God for 9/11”, “Your Pastor is a Whore” and “Fag Sweden”.

Fag Sweden and its Fag Vacuum Cleaners sold in the Fag Hardware Store. It totally makes sense if you look at it just the right way.

There is no question that their caravan of religious bigotry has made life miserable for thousands of people, many of them vulnerable mourners hoping to pay tribute to recently departed loved ones…

But the WBC also made life miserable for themselves and inflicted a distorted and poisonous view of the world on the youngest members of their own family, holding over their heads the threat that any deviation or failure of commitment (not going to a picket or socialising with outsiders) would result in a lifetime of banishment. Ex-members – of whom there are quite a few – can have no contact with the church.

Fred’s children, Theroux says, are nice people. The picketing is a performance as opposed to an expression of their character. But Fred was a different story.

Pastor Phelps was a different story: he was a hater by instinct.

I’m proud to say he took against me from the moment we met. I asked him how many children he had. He disliked this question – I think he found me trivial. The interview was cut short. Over subsequent days, we continued filming but I hardly saw him. I had the feeling he was hiding from me. We eventually crossed paths again, in church one Sunday after his sermon on the subject of America’s coming tribulations, in which he bellowed: “You’re going to eat your babies!” One-to-one, Gramps still had the remnants of a folksy, plainspoken charm, but underneath was a bitter contempt for humanity in general and me specifically. I asked him how he could possibly know that the WBC members were the only people bound for heaven. “I can’t talk to you – you’re just too dumb,” he said.

Poor guy – he probably would have been happier and more fulfilled as a hater on the Internet.