Yellowstone Supervolcano

My thought was to use geothermal power to draw heat from the magma plume so that when an eruption occurs, it is far less powerful. Some fairly small geothermal plants could be automated and (more, or less) easy to concele and could be distributed around the magma chamber.

there is archeological evidence indicating that the last time the Yellowstone caldera erupted it killed animals as far away as Kansas. The best way to minimize the risk is don't be there. Anything within a few hundred miles is going to be so screwed that light from screwed will take a year to reach them.

Excluding significant global damage, more than a third of North America would be damaged by an eruption, effectively crippling the U.S. and probably Canada. Because a volcanic eruption has multiple elements, primarily heat and pressure, current and foreseeable tech could not stop it. However, that doesn't mean the severity of the eruption can't be minimized by removing some of the heat.

Probably the best bet would be to figure out a way to detect and predict an imminent eruption and evacuate the area as much as possible. I don’t think there would be any way to prevent an eruption, and mitigation measures might help, but it would still be an extremely devastating event. I don’t know enough geology to know how accurate a prediction could be made, though. If it’s something like “it will erupt in the next hundred years” that would be a pretty precise prediction in geological terms, but practically useless in terms of evacuating people.

The current estimate of damage from an eruption would include ash fall as far as New York causing unknown damage and the Great Plains, where we grow our food, would be devastated. The immediate area, Wyoming, Montana, and Idaho, would get covered in several feet of ash.

So, while you're correct that we can't stop an eruption, evacuation would be problematic at best.

When it does erupt, it will be about like Mount Saint Helen x 1,000.

My question isn't how to stop it, but if it's possible to reduce the impact to something like Mount Saint Helen x 100, keeping the damage somewhat local.

You're saying you can get scientific data showing that a number of people are in imminent danger from something cataclysmic about to happen

And that the powers that be aren't doing anything about it

Sounds extremely far-fetched to me.