It is not every billionaire who can watch his dream project literally incinerate — at a cost of some $67 million — and deem it an “exciting” launch. But shortly after SpaceX’s Starship rocket blew up on April 20, following just four minutes in the sky, Elon Musk victoriously tweeted, “Congrats @SpaceX team on an exciting test launch of Starship! Learned a lot for next test launch in a few months.” It may not happen so quickly, especially with an expected FAA investigation. “I’d say three months is optimistic,” Douglas Messier, managing editor of ParabolicArc, a website that covers commercial...