For anyone who has lived in Chicago for a while, the Mexican Independence Day festivities, and the ensuing disruptions to downtown Chicago this past weekend, were no surprise. We’ve been trapped on DuSable Lake Shore Drive before, crawling along amid an exuberant group of celebrants waving the Mexican flag, honking their horns and feeling the September breeze on their faces.

It was a pain in the neck if you were trying to get home to a child and/or you couldn’t afford losing an hour or two to gridlock. But there are worse things in life than being stuck in the middle of a joyous, overwhelmingly peaceful carnival. When you consider that something like a third of Chicago’s population was either born in Mexico or has familial roots there, it’s hardly surprising that the Mexican Independence Day celebrations now are a big deal on the shores of Lake Michigan. And, let’s remember, we all have a constitutional right to gather in the open air with like-minded folks and ride down DuSable Lake Shore Drive in celebration.

If we keep moving.

There lies the rub. DuSable Lake Shore Drive can’t be a tailgating zone. For one thing, ambulances have to be able to get through.

Yet whereas most savvy Chicagoans clocked the calendar and made (or avoided) travel plans accordingly, City Hall appeared to be mostly oblivious to what happens every year now on this September weekend. Plans made in advance clearly were inadequate: The road closings, although necessary to prevent blockages, were last-minute, chaotic, unpredictable, poorly signed and mostly unannounced. And if you were visiting from out of state or even just from the suburbs, there was no noticeable pre-awareness campaign.

There were “lessons learned,” Mayor Brandon Johnson’s deputy chief of staff, Cristina Pacione-Zayas, told the Tribune. Sure. Good. But let’s not forget there were plenty of previous weekends just like this one that could have proved instructional.

Clearly, two things need to happen. The celebrants need and deserve more space and better accommodation, maybe in some kind of designated festive zone that we all know about in advance. And the city needs the mostly young flag wavers to understand that not everyone is having a party: Some of us are sick or trying to get to a job, and some of us are just trying to support a downtown business or event that can ill-afford another reason for its customers to be reluctant to go there.

The city has to focus its messaging along twin tracks: The right to assemble in joyous community celebration must be preserved, and lawlessness must not be tolerated.

This administration knows how to “lift up” the first (to use its preferred parlance) but not how to signal the second. The mayor needs to better understand that the one is as important as the other.

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