The National Ignition Facility at the Lawrence Livermore National Laboratory in California is home to the most powerful laser on the planet. It was intended to be developed into humanity's first break-even fusion generator, but it hasn't happened yet, and the new plan is to slow down the pace of fusion research. Again.
Here's an executive summary from the "National Nuclear Security Administration's Path Forward to Achieving Ignition in the Inertial Confinement Fusion Program:"
At present, it is too early to assess whether or not ignition can be achieved at the National Ignition Facility (NIF). However, a key goal of NIF to discover discrepancies between codes and experiments has been demonstrated clearly. The disagreement between NIF experimental data and codes and models reflects an inadequate understanding of key physics issues required to make this determination. The emphasis going forward will be to illuminate the physics and to improve models and codes used in the Inertial Confinement Fusion (ICF) Program until agreement with experimental data is achieved. Once the codes and models are improved to the point at which agreement is reached, National Nuclear Security Administration (NNSA) will be able to determine whether and by what approach ignition can be achieved at the NIF.
To me, that sounds less like a path forward, and more like a path sideways that pointedly de-emphasizes experimentation. And once you go down that route (especially now that so much time is being given over to nuclear weapon stability research), it's hard to get back time with the laser actually trying to make fusion happen, as opposed to just being told to plug some numbers into the computer instead. I may be being slightly pessimistic here, but still.
Look, fusion is hard. It's really hard. And it's entirely possible that NIF figured it would just be really hard, when it's actually really really hard. Congress, apparently, is pissed off that NIF has not made as much progress as it said it would.
But this is what science is.
You make a best guess, you try a bunch of different techniques, and sometimes, nothing works quite the way you want it to and everything ends up costing more money and taking longer. What you have to do, though, is look at what you're trying to accomplish, and what the risks and benefits are. NIF is expensive, that's for certain, but what's the potential return? Fusion power. Totally clean, virtually limitless energy. Global warming? Solved. Fossil fuel dependency? Solved. Environmental damage? Solved. Yes, that right there was a huge amount of hyperbole, but you get the idea: fusion power would put our entire species, our entire planet, in a much better place.
Or, you know, you can just whine that it's costing money and taking time and scale the whole thing back a bunch. The point is, even if this takes a hundred years of non-stop work, it's still going to be worth it when it's finished. And a hundred years from now, when we have working fusion power, people will be saying "thank the Flying Spaghetti Monster that our grandparents had the intelligence and foresight to start working on this a hundred years ago!" Except that, apparently, we don't.