The Day After Tomorrow by Robert A. Heinlein

This novel by Heinlein was one of my favorites, when I was younger. There was a whole genre that sprang up during the cold war about America being invaded by various totalitarian regimes and the fight of the underground against the oppressors. This one had a different twist to it, with the solution being found through superior technology.

The novel opens in a military research station in the Colorado mountains sometime shortly after the U.S. is overrun by PanAsian forces. The PanAsians instituted draconian controls over the populace, and any sign of rebellion is met with horrendous reprisals against civilians (like some of the prisoner camps in WWII). One of the experiments has gone wrong, killing off most of the personnel in the base, and Major Ardmore, from Intelligence, coincidentally arrives on the scene. The military is in shambles, and he has been instructed to tell the scientists at the base that they are to operate independently, using whatever means they've discovered, i.e., secret weapons, to route the PanAsian forces.

What they have been working on is a practical application of a theory that, like the electromagnetic spectrum, there are radiations or emissions in the gravitomagnetic and electrogravitic spectra that will have physical effects. In a practical sense, they come up with a death ray, a transmutation ray, a healing ray, a force field, and a few other things, as well. Unable to operate openly against the invaders for fear of reprisals, they decide to create a religion, the worship of Mota (Atom spelled backwards?). The PanAsians have a policy, based on previous conquests, of not interfering with their subject races' religions, so they allow this new one - they have no idea that it's actually brand, spanking new - to minister to the people.

With the transmutation ray, the priests of the new religion can create all the gold they need to buy supplies to feed the hungry. They're able to cure the sick with the healing ray, and they're able to guard their persons and property against the invaders with the force field. After some tweaking, they find that they can also specifically target the asian race with the death ray, while not affecting caucasians with it, due to genetic differences between the races. I think, given present genetic knowledge, that this is the place where Heinlein's story falls down for modern readers a bit.

We see here also a precursor to later novels, in that religion is used as a ploy to subvert and to teach those who can be reached. I still enjoyed it, after a long time since I last read it.