JEREMY LOTT: The future of space travel according to Branson, Musk, and Bezos.

As billionaires Jeff Bezos, Richard Branson, and Elon Musk use their private space exploration companies to shoot for the stars, they have been dogged by persistent, progressive criticism that this is all a highly combustible vanity project. “Billionaire Space Race: Shameless Vanity Projects in a World of Want” read one representative headline on the website Socialist Alternative.

But is it more than that? The Washington Examiner asked a rocket scientist for thoughts on what, if anything, these titans of industry are contributing to the future of space exploration.

“We are on the cusp of transition in space transportation comparable to the introduction of the DC-3 in aviation, or perhaps the transition from reciprocating engines to jets in commercial aviation,” said James Bennett, the chief regulatory officer for Immortal Data Inc. “The maritime analogy would be from sailing ships to steam in ocean navigation — perhaps the best analogy because steam changed the way everything was done in ocean transport.”

The man he pointed to as most responsible for this possibility is Musk.

Well, yes. Musk is almost single-handedly pushing the transition from command-economy space to economically sustainable space.

Plus: “Bezos thought he would be the tortoise and beat Musk’s hare, but he forgot that the rabbit has to stop for it to work. Instead, Musk is pushing on like the Energizer Bunny on methamphetamines.”