Fusion question

[Batman]

As we are apparently still as far away from achieving worthwhile fusion as we were half a century ago for hydrogen fusion to begin with this didn't seem appropriate for the S&L forum.
Assume you have the technology to use fusion as your main source of energy, up to and including fighters.
Fusion as used in SciFi generally means hydrogen and especially Deuterium fusion. So how about the stuff left over from that? Theoretically fusion of elements lighter than iron is a net energy event(though the energy needed to GET them to fuse would likely make that a net loss towards the iron end).
But COULD you use the helium resulting from hydrogen/hydrogen fusion to fuel another fusion reaction and so on?

[The Cleric]

Stars. If you can exert sufficient gravity, you can fuse anything.

[Batman]

With that kind of technology BOTHERING with fusion also becomes moderately pointless.

Let me try to clarify-with technology than CAN use H/He fusion as a safe and reliable energy source down to the single seat fighter level but does NOT have the means to ditch it in favour of direct/near complete e=mc^2 plants (Heinlein's matter converters, Trek's Warp core, Perryverse's NuGas reactors), is it possible and/or worthwhile to keep up fusing the leftovers of the LAST fusion cycle?