ITER is a research project that is costing more just to build, before any research happens, than a full-scale commercial production fission plant. (The scientists are not getting much of that. But somebody is.)
There is much that nobody knows about getting fusion working. What we can be confident about is that if ever made to work, it will cost way more than a fission plant of equal capacity. Fission is itself not competitive today, and gets less so every day.
A>B>C => A>C
Is this logic hard to follow? Cost of fusion is unknown, but already very large. Cost of renewables is known, small, and reliably decreasing.
50 years ago, you'd have told us to avoid developing weather satellites because we already have proven cheap anemometers. Obviously, that would have been a poor idea in hindsight, nevermind the tangential benefits of other space tech (satphones, GPS, etc).
Who is to say that fusion plants are necessarily going to remain as expensive as you claim them to be in the midst of another industrial revolution? This isn't a Wikipedia article for no reason: https://en.wikipedia.org/wiki/Fourth_Industrial_Revolution
You have to do research if you want the benefits thereof. Sure it can be expensive and time consuming... but investments have cost and risk. We're trying to get a big payoff, not save every possible cent in the now.
Also, I would argue that the building of it (and design of it) is of course part of the research, not "something that happens before any research can happen" as you said.
50 years ago, I was 100% in favor of making weather satellites. I was right, then, too.
What they are building at ITER lacks any apparatus needed for actually getting usable power out of the system. All of that is still completely theoretical, and needs, just for itself, decades of development work not even begun. Likewise, any of the apparatus needed to swap out parts of the reactor as they get destroyed by hot-neutron flux. That, too, has not even been started on, and will not be for decades. When ITER destroys itself, there will be nothing to do but bury it. They are not even prepared for that; is built above ground.
Read up on what capturing hot neutrons involves. The short answer is that it is all, necessarily, monstrously more expensive to build and operate than a fission reactor needs.
Fission reactors are not competitive today, and get less so every day. A reactor that costs 10x the equivalent fission plant will be even less competitive in 50 years, which is the earliest one could even conceivably be completed.
There is no plausible scenario in which Tokamak fusion ever becomes an attractive power generating option. Even orbiting solar-power satellites make more economic sense, and they are bonkers.
There are other, more plausible fusion alternatives, but there is no money for them. Tokamak eats all the fusion money.
The Tokamak research program makes sense only as a jobs program to keep hot-neutron physicists employed so there remains a pool to draw on for weapons work. It has no plausible product.
There is much that nobody knows about getting fusion working. What we can be confident about is that if ever made to work, it will cost way more than a fission plant of equal capacity. Fission is itself not competitive today, and gets less so every day.
A>B>C => A>C
Is this logic hard to follow? Cost of fusion is unknown, but already very large. Cost of renewables is known, small, and reliably decreasing.