Reporter Inga Saffron chatted with readers about this story and the reaction it received on Friday, September 30. See the full conversation here.

Watch out, Philadelphia. Here come the suburbanizers.

A mere four years after City Council approved a modern zoning code designed to encourage traditional urban densities and transit, two of its most powerful members are campaigning to take us back to the bad, old days when neighborhoods were hemorrhaging population, city planners were managing for decline, and the idea that Philadelphia would cease to be a real city seemed like a real possibility.

The first salvo in this regressive action came from Councilwoman Jannie Blackwell, who is pushing legislation that would double the amount of parking required in new developments. She was joined last week by Council President Darrell L. Clarke, who published a letter in the Inquirer that painted a bucolic vision for his district in North Philadelphia, replete with "spacious blocks, grassy lawns and gardens," and, by implication, long, private driveways. His aide Jeffrey Young chimed in on social media with calls for more car-friendly developments in African American neighborhoods.

Mayor Kenney's Planning Commission has so far held firm against their proposals to turn Philadelphia's tight rowhouse blocks into a 21st-century crabgrass frontier. Blackwell's bill, which would drive up housing costs, got a frosty reception at this month's commission meeting and was tabled for more review. But given Clarke's enormous influence on planning policy, it's unlikely Blackwell's legislation will die a quiet death. Should the duo get their way, this outdated philosophy could derail the dramatic progress Philadelphia has made in revitalizing its core neighborhoods.

Clarke wrote his letter in response to my Sept. 9 column on Sharswood, a massive urban renewal project in North Philadelphia that is being managed by the Philadelphia Housing Authority. My piece focused on the effort to bring back Ridge Avenue as Sharswood's main street, and I argued that PHA's plan would reduce that tattered, but still salvageable, shopping street to a car-oriented highway strip.

Because PHA has failed miserably every time it has tried its hand at retail development, I suggested the housing agency should outsource Ridge Avenue to an experienced corridor manager, similar to the organization that has made East Passyunk Avenue such a lively walkable place. If South Philadelphia isn't to PHA's taste, it can look at the work of the Nicetown Community Development Corp., which is reviving its stretch of Germantown Avenue with mid-rise apartments.

But not only did Clarke call my proposal for enlivening Ridge with stores and cafes "cringe-inducing," he also dismissed my "lofty standards for density" in the rest of Sharswood.

Arguing that the community, which is overwhelmingly African American, prefers a suburban lifestyle, he gave a shout-out to low-density projects in the neighborhood that feature single and twin homes. He suggested PHA's 1,200-unit Sharswood development should mimic that model. (Ironically, PHA is building only rowhouses in its first phase.)

I don't doubt that some residents there dream of having a house on a cozy patch of lawn. So do a sizable portion of all Americans. Philadelphia has many attractive, suburban-scaled neighborhoods, from Germantown to the Northeast. But that doesn't mean the suburban model is right for a neighborhood so close to downtown in 2016.

If you wander thorough Clarke's district, you can see several of these mini-suburbs. They are the legacy of the early 1990s, when Philadelphia was at its lowest point. In a desperate effort to stabilize places like Philadelphia, Washington policymakers encouraged cities to turn themselves into suburbs. Even high-rise neighborhoods, like the South Bronx, built their share of ranchers and Cape Cods.

Then the unexpected happened: Americans rediscovered cities. Philadelphia has attracted 80,000 new residents since 2006. What brought them here wasn't the suburban houses. It was density, the bustling street life and creative churn that you get in compact urban environments.

People also liked Philadelphia's transit options. Though nowhere as dense as Manhattan's, Philadelphia's rowhouse neighborhoods still have the critical mass of people necessary to support SEPTA's extensive network. That transit is crucial for connecting people to jobs. It also liberates people, particularly the poor, from the expensive burden of car ownership.

As Philadelphia has grown, private developers have built thousands of units to accommodate the newcomers. Mostly rowhouses, these homes mimic Philadelphia's traditional densities.

The surge in dense rowhouse construction is evident when you head up Ridge Avenue from Center City. Neighborhoods like Brewerytown and Francisville are attractive because they're so close to Center City - within walking distance if you're ambitious - and have terrific transit. It's clear that Sharswood would have been next up for revival (or, if you prefer, gentrification) had PHA not used eminent domain to take control of a large chunk of land from Girard to Cecil B. Moore Avenue, 19th to 27th.

PHA's strategy is to ensure that this pocket of Clarke's district remains affordable. Roughly 60 percent of the 1,200 units are supposed to be priced for low-income renters and buyers. Though there are reasons to wonder about PHA's ability to pull off the massive development, the concept makes sense because it secures land for subsidized housing before prices skyrocket.

The devil, of course, is in the details, and PHA's master plan is woefully short on them. PHA followed traditional density patterns with its first batch of houses - a mere 57 units - but it may decide to switch to suburban-style houses, spokesman Kirk Dorn said in an email.

Neither Clarke nor PHA seems to understand how their attachment to low-density development sabotages their stated goal of creating affordable housing. Yards and driveways will only drive up PHA's already bloated building costs. Where will the money come from? The agency, Dorn confirmed, is running a $21 million deficit and layoffs are being discussed.

While Clarke and Blackwell push their outmoded vision of a suburbanized city, President Obama is championing the opposite approach. This week, he issued a "tool kit" of ideas calling on communities to increase zoning densities to support the construction of more affordable housing. Obama may live in a big, suburban-style house, but he clearly understands how cities work in the 21st century.