‘I worry about school bathrooms,’ another commented. ‘That’s how those poor second-graders died in Miami. Thirteen in one year group.’

The drawler resumed his lecture. ‘We heard it all before with nuclear proliferation,’ he said, shaking his head slowly. ‘Everyone saying the terrorists would get a nuke. But detection systems were in place. SNor caught us with our pants around our ankles, but governments are on red alert now …’

Charlie had always seemed shy, so Harry was surprised to hear her butt in.

‘But the proliferation of nuclear weapons is difficult, because you need to enrich uranium ore into weapons-grade uranium,’ Charlie said. ‘Uranium enrichment requires a factory the size of three football fields, filled with thousands of gas centrifuges, each one more complex than a jet engine.

‘But I could go online and buy all the equipment I need to do gene editing for the price of a second-hand car, and the equipment would fit in a regular garage. So, you’re comparing two very different technologies.’

‘They’re clamping down on the sale of chemicals and equipment,’ the Texan said.

‘But tens of thousands of sequencing and editing machines have already been produced,’ Charlie pointed out. ‘And when all the rich countries ban the sale of gene-editing machinery, there will be dozens of poor ones, who either don’t legislate or don’t have the money to police it.’

One of the moms nodded. ‘It’s terrifying. I think about my three boys, and when I see it on the news … I know it sounds weak, but I turn it off because it’s so horrible.’

The Texan hated Charlie undermining his authority. ‘I’m sixty and I spent my whole life listening to people talking about threats. The communists were gonna wipe us out, then it was the AIDS, global warming, terrorists with nukes, terrorists with chemical weapons. All I know is I ain’t dead yet.’

‘SNor killed more people in six months than have ever been killed by terrorists and nuclear weapons,’ Charlie said. ‘I just researched it for my end-of-term paper.’

Now the guy roared with laughter, clutching his big gut. ‘Well, I gotta change my mind if you wrote it in your school pro-ject, sweetheart …’

A couple of the moms smirked too, and Charlie turned and scowled at Harry. ‘Screw this place. I’m outta here.’

‘He’s a pig,’ Harry whispered, grabbing her arm anxiously as she stormed away. ‘It’s nothing.’

But Charlie didn’t think so and headed for the exit. Luckily, a slim guy with a bouncy walk and a pocket full of pens blocked her path.

‘Welcome to Maker’s Yard. I’m Steve,’ he said, offering a hand to shake. ‘You must be Harry and Charlie. I’m sorry I had to pop out, but you didn’t say exactly what time you’d be dropping by.’

‘No probs,’ Harry said.

Charlie shook hands, but kept sulking.