This is not about weapons. That's a ludicrous viewpoint. We've been able to create fusion weapons for decades now by starting them with fission. There's no way to build a pocket fusion device so it would only ever be a giant nuke, which we can already build.
No, this is really real research. Oil and coal barons know the end is coming for oil and coal, that's why they're the primary card holders in renewables too. They don't actually need to burn fossil fuels, it's just more profitable to do so right now. Once it's not, they'll just turn to the next most profitable thing they've got their fingers in.