alt Hacker NewsFusion, I hate to say it, is a pipe dream. Why? Because any fusion reactor loses a ton of energy to fast neutrons, which have the added negative of destroying the reactor. So-called aneutronic fusion (eg using He3) isn't zero neutrons. It's just fewer neutrons.
Stars don't have this problem because they're very large so there's only so far neutrons can go.
This is such a weird thing to assume is just impossible in physics, I don't quite know how to respond other than "yes, there are many unsolved problems in every energy sector, which is why it's an open question where we go from here"