Bussard fusors...
Hi LJK
If Bob Bussard can ever get his modified Farnsworth Fusor to go above break-even then we just might see all those things. Else it'll be a long, hard slog to the Stars.
Or maybe not. Self-replicating solar-power satellites are technically not too far off. The project to build a rapid-prototyper that can build itself is one small step towards free-space von Neumann machines able to do the job. Perhaps they will provide the (effectively) unlimited energy interstellar travel will need.
Daedalus was a superb achievement of the mind, but we can do better (in theory) now and by 2050 we'll be able to do it in practice too. If we haven't cut our own fool throats with a greasy blade.
Adam