The nation’s homelessness problem has to a disturbing degree become California’s homelessness problem. While the latest counts compiled by the federal government show that America’s homeless population is growing again after more than a decade of declines, the entire national increase and more can be attributed to California alone.

With a majority of states experiencing decreases in homelessness over the past year and only one small state, New Mexico, suffering a larger proportionate increase, California’s dire statistics underscore the extent to which state and local policies drive an extraordinary and persistent failure to shelter the equivalent of a midsize city. Although the state has the worst housing shortage on the U.S. mainland, resistance to dealing with it remains endemic among the Legislature’s ruling Democrats and in nominally progressive cities such as San Francisco.

Based on a January census widely believed to underestimate the true figures, the U.S. Department of Housing and Urban Development reported Friday that the nation’s homeless population grew by about 15,000 people to about 568,000, or 2.7%. The number of Californians without homes, meanwhile, spiked by more than 21,000 to over 150,000, or 16.4%. The state’s exploding homelessness was enough to overwhelm declines in 29 states, among them Washington, Hawaii, Massachusetts and other states with substantial housing pressures.

While the nation’s homeless population remains about 10% lower than it was a decade ago, California’s has expanded more than 22% in that time. With less than an eighth of the U.S. population, California is home to more than a quarter of the nation’s homeless people and more than half those who are unsheltered.

More remarkably, the ranks of homeless Californians continue to expand even as overall growth has slowed to a trickle. The state Department of Finance estimated Friday that California’s population grew only 0.35% over the 12 months ending July 1, the smallest increase since 1900, with Marin, Sonoma, Napa and Santa Cruz counties among those that lost population. The slowdown was fueled by residents leaving California for other states, who outnumbered those arriving from other states and countries for the first time since the beginning of the decade.

HUD Secretary Ben Carson said in a statement that “homelessness in California is at a crisis level and needs to be addressed by local and state leaders with crisis-like urgency.” Led by President Trump, administration officials have threatened a crackdown on the state’s homeless.

Gov. Gavin Newsom and other California officials don’t tend to appreciate advice from the Trump administration, which based on its record so far seems more likely to play the state’s troubles for political gain than to make any constructive attempt to address them. That said, Carson is right: The state’s response to homelessness isn’t equal to the human disaster at hand.

Study after study has demonstrated the strong relationship between housing scarcity and homelessness, but the Legislature hasn’t passed a comprehensive measure to expedite residential development since 2017 and has repeatedly shelved the most significant measure in play, SB50. The San Franscisco Board of Supervisors, typifying the approach of too many local governments, voted against the measure for the third time last week.

Beyond legislation to speed development, the state’s rampant homelessness calls for reform on the order of the right-to-shelter policy backed by the leaders of Newsom’s task force on the issue — though not, so far, by Newsom himself. Anything less will enable more demagoguery and suffering.

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