Alas for Detroit, there was no presidential statement of purpose, no outpouring of American sympathy, after the Census Bureau reported its own calamity: the shrinking of the city’s population to just 713,777—a level not seen since around the time Henry Ford started cranking out the Model T. In Detroit, of course, we do not see lives being lost to an angry and capricious Earth. But the human wreckage is there all the same—the consequence of crime, strangled opportunity, and lives without hope.

Most Americans did not need to be told that Detroit is in a bad way, and has been for some time. Americans know all about white flight, greedy unions and arrogant auto executives. The recent census numbers, however, put an exclamation mark on a cold fact: A once-great American city today repels people of talent and ambition.

“Detroit is a classic example of how a culture that was legendary for enterprise and innovation was slowly eroded by toxic politicization from the 1960s on,” says the Rev. Robert A. Sirico, president of the Michigan-based Acton Institute. “It’s been class warfare on steroids, and the inevitable result is that so many Detroiters who had the means—black and white—have fled the city.”

Another way of putting it is this: Unlike New Orleans and Japan, the ruin we see in Detroit is entirely man-made.

It wasn’t always this way. For years, Detroit was a synonym for American energy and opportunity. Here Motown Records was born and General Motors became the first company to make a billion dollars in a single year. And here the auto industry that we now think of as geriatric drove the American economy, helped create the American Dream, and defined American culture to the world.

“Detroit was a mecca for automotive entrepreneurs back then, just as San Jose is for Internet innovators today,” says Paul Ingrassia in “Crash Course: The American Automobile Industry’s Road from Glory to Disaster.” Mr. Ingrassia, a former reporter in this paper’s Detroit bureau, was writing about the early part of the 20th century. But even years later, Americans spoke of the Big Three the way we today speak of Google.

What happened to this Detroit? In many ways the answer is liberal politics and expanding government. In the 1960s, for example, Detroit became one of Lyndon Johnson’s “Model Cities.” That meant it was on the receiving end of hundreds of millions of federal dollars to transform a nine-mile-square section of the city. It would be just the first of many government-funded redevelopment schemes that left behind one of the most blighted urban landscapes in the nation.

Notwithstanding its failures, government continued to grow while city services—e.g., police and fire protection—continued to decline. Whites moving to the suburbs took much of the tax base out of the city in the 1960s. The latest census numbers show that blacks are now following in the path of the whites before them. Apparently they don’t like crime and the lack of decent schools for their kids either.

What’s left is the city so embarrassingly exposed by the census figures, a place that people are fleeing as fast as they can. Think of all the dysfunctional measures you can: poverty rates, unemployment, crime, failing public schools, falling home values. Detroit has them all, and most of its indicators rank among the worst in the nation.

Mayor Dave Bing, God bless him, is trying to change this. He’s a decent man with an almost inhuman task. So it was discouraging to see his reaction to the census. Because falling under 750,000 in population means Detroit will no longer qualify for certain federal and state aid, he has fallen back on the hack political response: Demand a recount.

Whether Detroit can come back isn’t the question. Of course it can. But it will take far more than an edgy, “Made in Detroit” Eminem ad for Chrysler. The test will be a reverse of what we saw with this latest census report: That is to say, a Detroit that is welcoming new waves of immigrants and small business owners, selling homes to families who buy because they think the neighborhood has potential, not to mention persuading University of Michigan and Michigan State graduates now flocking to Chicago to build their futures in the Motor City instead.

What’s happened to Detroit is sad. Sadder still is that though the human dimensions of this tragedy are as cruel as any earthquake, they elicit so few second thoughts.

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