I can't say I'm optimistic that it would have led to any sort of fusion power, but it could have encouraged more people to go into physics knowing there was a well funded jobs program for it.
Also, it's possible we might have a spinoff technology to show for it all.
For example, the VASIMR thruster that has been going nowhere for two decades was a spinoff from MCF research.
Maybe we could also have a Z-pinch spinoff thruster and a pulsed laser thruster going nowhere for decades.
nyrath