Helium-3 is why we need a permanent presence on the Moon, the theory is that the surface is covered with it.
It probably is, but first we need a market for it. Than't won't happen until the perfect fusion.
It is not a question of lack of tech at this point it is a question of scaling. There is no known issue with scaling it to commercial levels at this time. How ever we have thought this before when scaling other tech and then we go and do it and discover these issues. I am very excited but we wil not know if there is no issues with scaling unti we actually do it. We are in this process right now. It will be five years till the first large reactors are made and put into testing. My fingers are crossed. This could be a real game changer as to what humans can actually achieve. I do not know how old you are but if you are younger than me there is a real possibilty that fusion will be online and astroid mining will be a norm in your life time.
MIT and Rockwell are working on smaller reactors that use superconductors to create the magnetic bottle. They won't need to be "scaled." Still, until this technology is perfected, there's no market for Helium 3.