If Ald. Matt O’Shea is able to follow through with his plan to annex Mount Hope Cemetery, it would be the first time Chicago’s borders have expanded since the mid-20th Century. That’s when we absorbed O’Hare Airport, as well as a forest preserve and a stretch of Foster Avenue to connect it to the rest of the city.

Meanwhile, the cities of the Sun Belt have continued to expand into the 21st Century, so much so that Houston is now threatening to bump Chicago from Third City to Fourth City by population. Like most Northern industrial hubs, Chicago’s growth ground to a halt decades ago. Why did we stop growing, and can we ever grow again?

In the late 19th and early 20th centuries, Chicago grew into a great metropolis by gobbling up suburbs we now know as city neighborhoods. In the 1880s, the city limits were bounded roughly by Fullerton, Pershing, and Pulaski.

Then, Chicago landed the Columbian Exposition, which was envisioned as our coming-out party as a world-class city. At the time, Chicago only had 500,000 people, making it the fourth-largest city in the U.S. That wasn’t enough for our ambitions. We wanted to challenge New York.

In order to become the Gotham of the Great Lakes, the city’s leaders approached the residents of four bordering townships: Lake View to the north, Jefferson to the northwest, Hyde Park to the south, and Lake to the southwest. Join us, went the offer, and you’ll get better police and fire protection, better water and sewers, better roads, and the prestige of a Chicago address.

In 1889, all four townships voted themselves into the city, doubling its population and making it the nation’s second city, behind New York. (In Hyde Park Township, workers at the Pullman Palace Car Company were eager to dissolve the “company town” established by their bosses.)

“The city had better supplies of water, city services, and these suburbs couldn’t compete,” said Dominic A. Pacyga, author of Chicago: A Biography.

(New York, which at the time consisted only of the island of Manhattan, responded by amalgamating with four surrounding counties, building a five-borough city whose population was beyond the reach of Chicago.)

In the years following that mass annexation, Chicago added bits and pieces along its borders: Rogers Park and Norwood Park in 1893, Edison Park in 1910. (The latter was won by Chicago’s new Schurz High School, which was easier to get to than neighboring Maine Township’s.) Mount Greenwood was the last major residential neighborhood to join the city, in 1927.

Annexation ended for two reasons: the city was growing too large and unwieldy to manage, and it hit a wall of suburban resistance. We courted Oak Park and Evanston, but, with well-established identities as railroad suburbs, they turned us down. The Metropolitan Water Reclamation District allowed suburbs to buy water from Chicago, and neighboring towns developed their own city services, often better than Chicago’s. Then, in the white flight era following World War II, suburban addresses became a class symbol.

“Once the smaller suburban communities figured out how to provide water and sewer and high schools, they went on their merry way,” said Ann Durkin Keating, professor of history at North Central College.

Cleveland stopped growing in 1923, and Detroit in 1926. But that hasn’t been true of all Northern cities. Indianapolis merged with its suburbs in 1970. Columbus has grown into the largest city in Ohio by requiring annexation in order to join its water system. Even here in Illinois, Decatur has been grabbing unincorporated land to make up for population losses resulting from its flailing industrial base.

Down South, Houston has expanded to 662 square miles — nearly three times Chicago’s size — by ruthlessly grabbing every piece of land in the path of its growth. Thankfully, even Houston is slowing down, due to a new Texas law requiring cities to get permission from the communities they annex.

That’s the law in Illinois, too. Even annexing Mount Hope Cemetery, which is in an unincorporated area and contains no voters (we’ll spare you the joke about dead people voting in Chicago), would require an act of the legislature. Those barriers mean Chicago’s borders will likely remain fixed.

“There was talk a few years ago: ‘Why doesn’t Evergreen Park become part of Chicago? Why don’t the inner-ring suburbs become part of Chicago?’” Pacyga said. “It’s more expensive to live in the suburbs, but you get this feeling, ‘I live in the suburbs.’ It’s a social class thing.”

Chicago doesn’t have the motivation to grow, either, according to Pacyga. The city makes more money selling its water to suburbs than to its own residents. Struggling suburbs such as Riverdale and Dolton might benefit from joining Chicago, because their property tax rates are so much higher than ours, but absorbing another municipality could be a strain on the city’s budget.

Lastly, there’s the issue of cultural identity. As we learned in the great “bruh” debate of 2017, Chicagoans have a nose for suburbanites claiming the city as home. (You can even take a quiz about it.)

In the Cash Box Kings’ song “Joe, You Ain’t From Chicago,” a narrator in the song’s opening skit calls Johnnie’s Italian Beef “the best beef place in Chicago.”

“Joe, that ain’t Chicago,” he’s told. “That’s Elmwood Park.”

For now, that’s not going to change.