Mayor Lori Lightfoot, in a speech to the Economic Club of Chicago on Monday proposed a 10-year growth plan with an ambitious goal: increasing the city’s population to 3 million from 2.7 million.

She was vague on how to get there.

The mayor wants to focus on four growth industries: transportation, distribution and logistics; technology; tourism and hospitality; and healthcare and life sciences. She also urged her listeners — an elite group of civic and business leaders — to support INVEST South/West, a previously announced initiative to revitalize 10 neighborhood commercial cores on the South and West Sides.

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These are good ideas, well worth pursuing. But they won’t, in themselves, lead to population growth.

To understand what will, we need to get a firm handle on the problem.

It’s not that Chicago does not attract people. Of the city’s four major racial or ethnic groups — Asians, blacks, Hispanics and whites — three are growing in numbers at a healthy pace. The only group in demographic decline is the African American community.

There are two reasons some parts of the city are growing.

The first is that downtown Chicago is creating new jobs at an impressive pace. Since 2010, it’s added 140,000 workers.

The mayor is right to want to keep stoking Chicago’s growth engine. The city is a proven talent magnet. The four industries she’s picked as growth opportunities make perfect sense. Say what you will about former Mayor Rahm Emanuel, he was a terrific sales rep for the city. Lightfoot needs to do the same.

Second, the vast majority of new workers in downtown Chicago since the late 1990s have chosen to live in the city.

That may not continue indefinitely, especially if the costs of city living continue to rise. But the immediate concern is the shrinking of Chicago’s African American community.

Every other major ethnic group in the city is growing at a healthy rate, primarily because we’re the chief draw for college graduates in the central United States. If Chicago’s black community were to grow at the same pace as the rest of the city (roughly 0.9% annually), we’d hit the 3 million mark in 12 years.

Realistically, that’s not going to happen. Current projections are that Chicago’s black population will continue to drop, offsetting the growth of other ethnic groups.

You can get an argument about why black people are leaving Chicago. But few will dispute that the root cause is the perception that African Americans can’t get ahead in this town. If you’re black and looking for opportunities, you’ve got to go someplace else.

The obvious way to turn that perception around would be the emergence of a stable, high-profile middle-class community that was predominantly, though not entirely, African-American.

Such a community already is coalescing. It’s on the south lakefront.

As I have written before, the south lakefront redeveloped rapidly after high-rise public housing was torn down in the 2000s. Black college graduates were the major driver of this growth. The recession brought that to a halt, but property values have slowly recovered. Redevelopment is resuming.

The south lakefront is the closest thing we have to a can’t-miss opportunity. It was once a wealthy area and still looks the part. It’s on the lake. It’s close to downtown, major cultural and recreational venues, and good shopping. The Obama Presidential Center — fingers crossed — will be built there.

A redeveloped south lakefront would be a beacon to black college graduates throughout the rest of the country.

The south lakefront is just one part of the city. But you have to start somewhere.

Forty years ago, most of Chicago’s white college graduates lived on the north lakefront. They gradually spread over much of the North Side. The same thing would likely happen on the South Side.

How long would it take for black flight to end and the city’s overall population to reach 3 million?

I have no idea. But barring a major resumption in foreign immigration, which isn’t in the cards at the moment, reversing black flight has to happen for Mayor Lightfoot’s vision to become reality.

That’s not to throw cold water on the idea. On the contrary, we need to get started right away.

Massive government intervention isn’t necessary; the middle class for the most part can take care of itself. What’s needed is careful planning, shrewd investment and a clear-eyed grasp of how urban growth works.

Ed Zotti writes City at the Crossroads, a biweekly Sun-Times column on Sundays that looks at trends affecting Chicago and choices the city faces.

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