Currently Quantum computers might be where Rockets were at
the time of Robert Goddard:
"If quantum computing is at the Goddard level that would be a good thing for
quantum computing. This means that the major fundamental breakthrough that
would put them over the top was in hand and merely a lot of investment,
engineering and scaling was needed."
See:
http://nextbigfuture.com/2015/07/cur...-might-be.html