Err-Fz forgive me..I don't know where rocket came from (tiredness perhaps?) but what I meant was not really fuel, but a fuel source-such as you said, the fusion.
Helium-3 is a very viable source of fuel: "extremely potent, nonpolluting, with virtually no radioactive by-product."-Julie Wakefield
Actually, there is a very large amount of wealth to be found in close space, and a very good reason to colonize both Mars and the Moon. For example, the Moon itself contains a very rare element found on earth-Helium 3, which could be used in a multitude of ways, such as rocket fuel...
Forgive me if this has been answered elsewhere on the forums, or if there really is an answer out there. I am a High School student and have been bothered by this problem for quite some time, so I was wondering if someone here could possibly help. Please though, I'm just a High School student...