Sure, but five orders of magnitude worth of liberties? The Orion spacecraft concept you mention will use fission bombs on any vehicle we might build soon. The

Sure, but five orders of magnitude worth of liberties? The Orion spacecraft concept you mention will use fission bombs on any vehicle we might build soon. Thermonuclear driven interstellar Orion has been proposed, but the vehicle would be enormous (and take 400 years to reach the nearest star.)