When the violence and rioting broke out in Baltimore shortly after 3 p.m. on Monday, it continued virtually unabated as police looked on helplessly. More than a handful of protesters eagerly remarked to the members of the news media filming the spectacle that they were shocked by the level of deference the police allowed to the rioters. And it was shocking.

One of the reasons for Baltimore’s pathetic ill-preparedness was, as Mayor Stephanie Rawlings-Blake insisted, because they simply did not see this coming. But the city had all the warning in the world.

Clashes between police and gang members erupted in the days leading up to Monday’s violence in response to the death of Freddie Gray. A Baltimore Police Department memo released before noon yesterday warned that “credible information” indicated “gangs including the Black Guerilla Family, Bloods, and Crips have entered into a partnership to ‘take out’ law enforcement officers.” And, of course, there was the raging violence that exploded on Saturday when formerly peaceful protesters vented their hatred on those attending an Orioles game at Camden Yards stadium.

That video is positively nauseating, and the terror reflected in the eyes of the people attending that baseball game is palpable. Rather than seek out this video and the others that surely emerged from this horrible event, cable news commentators self-consciously defended their networks’ decisions to broadcast a fancy dinner party in Washington D.C. instead.

The media’s disinterest in the violent unrest incubating in Baltimore certainly played a role in the disaster on Monday, but the press is by no means solely to blame for this lamentable episode. It was the city that dropped the ball.

“The first lesson in these crises is control the streets, protect businesses and citizens, and don’t let anyone congregate,” former Boston Mayor Raymond Flynn wrote of the lessons he learned dealing with an outbreak of riotous violence in 1990. “You have to anticipate the city will be volatile.

We knew who the criminals were and moved them away from the business district. They couldn’t get near liquor stores or pharmacies that sold drugs. A mayor must review all these lessons from other cities and tap into professionals with experience.

The black community also deserves to have a police command staff that reflects the diversity of the city. You need to have credibility in the neighborhoods. That’s what I did — promote the same guys who coach Little League and collect the donations in church.

This is all good advice, but none of what Flynn recommends is proactive or preventative. His are recommendations for how to respond to violence that has already broken out and can only be contained.

What would have happened had the news media broadcast this and other videos of the attacks on baseball fans on Saturday? What if those images had captured the media’s attention rather than a roast of the outgoing President of the United States? What would this city, its detached mayor, and its languid police department have done if on Saturday the nation recoiled in horror at this display of brutality? It’s unlikely that the city and its mayor would have shrugged. In fact, it’s quite possible that a forward positioned and robust police presence might have averted the tragedy that occurred yesterday in Charm City.