As it happens, most of California’s outward-bound migrants are low- to middle-income, with relatively little education: those typically employed in agriculture, construction, manufacturing, hospitality and to some extent natural-resource extraction. Their median household income is about $40,000—two-thirds of the statewide median—and about 95% earn less than $80,000. Only one in 10 has a college degree, compared with 30% of California’s population. Roughly 40% of the people leaving are Hispanic…

For starters, zoning laws, which liberals favor to control “suburban sprawl,” have constrained California’s housing supply and ratcheted up prices. As Harvard public-policy professor Daniel Shoag documents in a working paper, land restrictions became common in high-income enclaves during the 1970s—coinciding with the burgeoning of California’s real-estate bubble—and have increased income-based segregation and inequality.

Housing in California is on average 2.7 times more expensive than in Texas. The median house costs $459 per square foot in San Francisco and $323 in San Jose, but just $84 in Houston, according to chief economist Jed Kolko of the San-Francisco based real-estate firm Trulia TRLA +14.01% . Housing in California is cheaper inland than on the coast, but good luck finding a job. The median home in Fresno costs $95 per square foot, but the unemployment rate is nearly 15%, compared with 6% in Houston.