Why support focus fusion?

Why not is the better question.

Maybe an economic collapse won't be avoided.  Certainly, focus fusion won't prevent one.  However, it may help enable a recovery.

We should already have molten-salt reactor technology.  I'm thinking it was blocked because the powers-that-be cannot wrap their minds behind the idea that energy prices must fall.  Instead, they are blocking new energy ideas so as to keep us on the old system, which is failing us.  It could fail in a spectacular fashion.

The reason for the failure is the zero-growth mindset that views the inventions of mankind to be some type of problem that must be solved as opposed to the inventions being the solution.  One of those solutions was a molten-salt reactor, which could have given an energy price cheaper than coal and cleaner than any fossil fuel technology now in existence.  What about nuclear wastes?  With a molten-salt reactor, the wastes could be reduced by two orders of magnitude.  Certainly, an improvement worth pursuing, right?  Wrong.  It could replace existing big energy companies, and these guys don't sit around idly and let their fortunes be destroyed by the new tech.  So, the new tech is suppressed.

Cold fusion and now aneutronic fusion is a couple more technologies that the "leadership" isn't much interested in.  Not because they won't work, but because there's a good chance that they will.

That's what people need to wrap their minds around.  They've got this idea that the government is working in their interests.  Wrong.  They are working in their own interests.

Energy is the key.  With cheap and abundant energy, many things become possible.