Actually, I think the National Ignition Facility will have no trouble in getting net power out, very soon. The real challenge is getting a significant amount of power out at some non-insane cost, since the NIF in its present form costs billions of dollars and can only do one fusion shot every couple of weeks.

The NIF's plan for a commercial inertial confinement fusion reactor looks like the NIF, except that shots occur ten times a second. At the moment they have no way of firing the lasers that often, or of extracting all the energy thus produced.

Is NIF getting close to breakeven in terms of laser input energy, energy generating the lasers, or thermal energy to power a turbine to power the lasers? Because, useful power generation requires ~30-100x breakeven in terms of laser energy and last time I checked they where several orders of magnitude from that standpoint.

Fusion has been "the biggest scientific breakthrough of the next 10-20 years" since I before I was a teenager 35 years ago. Like AI, it has become an "I'll believe it when I see it" technology.

The difference between what's going on with fusion today and what was going on when you were a teenager is pretty huge, actually. When you were a teenager there wasn't a gigantic international consortium (ITER) dedicated to making fusion happen in our lifetimes. The US government effort was limited to fringe experimentation; in contract, today, the NIF and France's Laser Megajoule are both aiming for net power out in the next few years. And, perhaps more importantly, unlike in the 80s there are now private startups looking to commercialize fusion processes -- that wasn't even being seriously considered 10 years ago.

Just because there isn't net power out today doesn't mean that an enormous amount of progress hasn't been made.

This touches upon another important point: fusion has never received the amount of funding it should have received in order to make true on their claim. It would have been available right now if only countries would have freed up reasonable amounts of funds. The JET project in the UK was extremely succesful and it is completely incomprehensible that it wasn't followed up upon swiftly and strongly. I believe lobbying by those invested in traditional sources of energy has everything to do with that.