WALL STREET JOURNAL: Liberal Cities, Radical Mayhem: Democratic mayors and governors seem unable to stop the destruction of their own cities.

The “broken-windows” school of policing says that you can help maintain public order by taking care of even small examples of disorder—such as fixing broken windows. Liberals scorned that policy in the last decade as somehow racist. Well, in recent days we’ve learned that America’s left does have a broken-windows policy: Let rioters break enough windows and loot enough stores and maybe their righteous anger will be satisfied.

That’s certainly how it looked when the June sun rose Tuesday over the broken glass, looted storefronts, burnt-out cars, and vandalized buildings in New York, Philadelphia, St. Louis, Madison and other American cities. Public officials let rioters exploiting the memory of George Floyd run wild in the streets. Even after nearly a week of violence, these and other liberal Democratic cities let lawless radicals harass and plunder almost at will.

In downtown St. Louis, four police officers were shot after midnight. “I believe some coward randomly shot at the police line,” said police chief John Hayden. A 7-Eleven was looted and set afire, but firefighters were deliberately slowed by protesters in responding. “We had people lying down in the street” and trash cans were placed as obstacles to block fire trucks, said fire chief Dennis Jenkerson.

In Philadelphia, city of brotherly vandals, gangs of rioters rolled through several neighborhoods Sunday burning businesses and cars. They returned for more on Monday, shutting down the highway that bisects the city at evening rush hour.

Police Commissioner Danielle Outlaw said a crowd of more than 100 surrounded a lone state trooper inside a vehicle and began rocking it. When two SWAT teams arrived, the crowd pelted them with rocks from the road and above. Police had to fire spray pellets, bean bags and tear gas to escape. . . .

This isn’t merely about damage to property. It’s about destroying the order required for city life. Non-criminals are afraid to go into these cities to make a living. The police pull back from active policing, which creates more opportunity for criminals, especially in poor and minority neighborhoods. Businesses that are finally starting to emerge from government lockdowns have new costs to absorb and more reasons for customers not to return.

What all these cities have in common is that they are led by Democrats who seem to have bought into the belief that the police are a bigger problem than rampant disorder. They are either cowed by their party’s left, or they agree that America is systemically racist and rioting is a justified expression of anger against it. They offer pro forma disapproval of law breakers but refuse to act to stop them.

The upshot is that a message is being received — even by those loudly posturing as woke at the moment — to the effect that you and your properties aren’t safe in big blue cities, and maybe even in medium-sized ones. All the talk about the reurbanization of America just went up, literally, in smoke. Thanks to the pandemic, cities were already looking like centers of disease. Now they’re looking like centers of violence, too. As I said earier, three decades of image rehabilitation for big urban centers has been undone in just a few weeks.