After Tesla Inc. (TSLA-Q) reported disastrous quarterly financial results this week, Elon Musk vowed to step back from his government cost-cutting efforts in Washington and devote more time to leading the EV maker. Oh dear. The mainstream bullish case for Tesla has traditionally rested on three pillars: corporate leadership that basked in the aura of genius, U.S. government policies that incentivized electric vehicles and enthusiastic consumers who delivered strong car sales. Now, these pillars are wobbling, leaving Tesla’s steep equity valuation out of line with the company’s slumping performance. This week, the EV maker reported that its first-quarter profit fell...