So helium is a limited resource. Okay gotcha. So why not take two hydrogen atoms. Take their protons and neutrons. And just fucking start squeezing them together until you get helium?
And I don’t mean in the same way you get H2. Those are still separate from each other.
Not the really the “same reason”. Unless that reason is the in both cases, the binding energy per nucleon is increasing. So, for interested people, also look at the binding energy per nucleon curve. Fe is boring…but stable.