[Suicide Junkie]

Trying to use helium3 from the moon to power all of earth is just plain silly.
In the exact same way that sending a copy of everything in the library of congress down your superfast internet connection is silly.

Having a mobile moon reactor, which does the fusion, scoops up dirt and uses the waste heat from the reactor to bake out the He3 sounds much more efficient. And collects oxygen for the moonies at the same time.
It could even be a tunneling drill-thing to gain protection from natural bombardment.

Of course, the energy density *is* high enough that shipping it to earth could be very lucrative; billions of dollars per ton, supposedly.