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I read a novel around 2000 where a scientific discovery of some sort of field effect (?) made it possible to build devices that would prevent gunpowder from working over a large area.
I think it had a one word title. "Primer" and "Damper" spring to mind, but I've checked, and can't find either. It was a trade paperback about the size of Jurassic Park. I think it just had a generic explosion behind the title.
I think the book was divided into three sections for three different uses of the field. I don't remember what the first was. The second was the anti-gunpowder field. The third was very short, and demonstrated selectively killing one baby mouse. I think the explanation was each object has some fundamental vibration, and getting a piece of fur let you tune to exactly that frequency?
I remember a few set pieces.
One was some sort of gun-control debate, about whether this device should be banned. The designated villain pulled a gun out of his podium to threaten someone and announced that the field covering the building had been sabotaged, and the protagonist debating him realized that they had only chosen podiums at the last minute, so found a gun in his as well. Which was apparently the villain's plan all along, so that he could prove that only guns could stop him? The logic was a little convoluted.
Another, later set piece was that survivalists had kidnapped the inventor. He discovered that since guns wouldn't work, they planned to defend themselves with saran gas. The military raided them before they could get that ready though. Each side was using crossbows.