>>633>Are these limitations not just solvable engineering problems which could have easily been fixed in top-secret nuclear R&D by now?<Fusion "Fizzle" bombFor fusion to occur the nuclei of the elements you're intending to fuse have to overcome the coulomb barrier. This is a extremely powerful electrostatic force (because positively charged protons) that prevents them from touching. The type of atomic bombs that use fusion, go the
thermonuclear route. Which means adding insane amounts of heat-energy under conditions of insane pressure, and then atoms bump into each other so hard that they overcome the coulomb barrier and their nuclei fuse. In practical terms a chemical explosive sets of a little fission-bomb that sets of a big fusion bomb. The "detonator cap" is a little nuke all by it self. That's how hard it is to set of a Fusion bomb. I don't see a practicle way where you can maintain these extreme conditions for long enough to make fusion "fizzel". At least not in a form factor that fits into a bomb.
There are however theoretical ways, like for example muon catalyzed fusion or antimatter induced fusion.
If muon particles participate in the fusion reaction the temperature requirements for fusion goes down dramatically. To the extend that you could make it happen in a combustion engine. However, practicle muon generators that make "long-lived" (a few milliseconds) muon particles is the realm of science fiction as far as i know. If anybody is hording knowledge of such a device, they would be crazy evil, because it's also one of the key components for building something like a "healing ray" that can cure a thousand diseases, with zero negative side effects.
We can make antimatter, but it would be ludicrously expensive (orders of magnitudes more than any military could afford), and anti-matter storage tanks can only store it for a short time. Nobody is hiding anti-matter reactions, those generate particles that you can detect while on the other side of the planet.
<stealthy beam weaponsIn the vacuum of space, sure, inside an atmosphere, no way. No matter what type of energy you choose, if you have enough of it, you will disturb the molecules in the air enough to make them emit some kind of radiation. Air is mostly nitrogen and most energy types will cause it to ionize and emit loads of UV and shortwave blue light.
You're intuition about powerful nuclear beam weapons based on a cartridge that is conceptually related to nukes is correct, that is doable and likely being researched. However that is something you put on a rocket to shoot it into space, where you use it to deflect asteroids on a collision course with earth. Aim the giant atomic space ray at the asteroid to vaporize a part of it, and the evaporates/ejecta act like a rocket booster to make it change course.
I guess you could make nuclear pumped x-ray lasers and then frequency shift it down to a more useful and less nasty wavelength. It's not really stealthy by any means but less in your face obvious as the other ones.