Oh, I believe working fusion reactors are in the very near future, without a doubt. However, I also believe it can't possibly work out to be as transformative as people seem to expect. In the end, we'll be saying "congratulations, you've developed the most expensive form of energy production yet! It's nearly useless!"

And worst of all, we don't have enough beryllium in the world to produce the fusion breeding blankets needed to make more than a few fusion power plants. And even if we could make all those shiny beryllium blankets, we then have another problem... one of the side effect of using a heavy metal to absorb high energy particles and turn then into heat, is that over time the entire blanket becomes highly radioactive. Now we're back to the same problems we have with fission, but at a much higher cost.

Will fusion work? Absolutely, and it will be extremely useful for long duration space missions, or antarctic bases. But beyond edge cases, the tokamak will probably never make sense.

I'm curious to see if other solutions like helion's reactor will work, that certainly seems a lot more sustainable.