Well, the French and the Japanese are fighting over who gets to build the next experimental fusion reactor.
http://www.csmonitor.com/2004/1209/p15s01-stss.html
The thing only costs $5 billion. I say we build one right now while they squabble. Hell, we'd just have to put some useless military program on hold for a few weeks to pay for that. I can think of a couple programs that are significantly less likely to ever work than a fusion reactor - missile interceptors & "bunker busting" nukes.
I agree. If fusion reactors can actually work, be safe, and be economical [produce more power than required to sustain the fusion reaction]... we would be poised to phase out all other types of large-scale electricity generating plants... and have a non-OPEC, non-polluting source of power to create hydrogen fuel.
Only remaining question is what we'd do with all of that helium. Maybe fill bladders in automobiles to make them lighter and improve our "hydrogen gas mileage."