What a difference 50 years makes. Back in the late 1950s and early 1960s, Bangor took the plunge on urban renewal, an invasive form of economic development that was widely accepted then as the right treatment for the blight that ailed hundreds of communities around the country.

The cure was worse than the disease, though. The strip of land along the Kenduskeag Stream and beyond was cleared, but it took decades for new buildings to finally be constructed. And beautiful old structures that today would have developers drooling over their commercial and residential potential were crushed into the dust of history.

That’s the CliffsNotes version of the urban renewal in Bangor. The full story is more complex, and was explored in a three-part series by former BDN Assignment Editor Tom McCord in 2009 and 2010.

Now, with the wisdom of hindsight and the fiscal reality of these post-recession times, the Bangor City Council is again embarking on revitalizing a portion of the downtown. It won’t take on big-ticket expenditures like purchasing property, but there are steps it can take that, if executed properly, can start a chain reaction that will transform a neighborhood. A little luck would help, too.

The nature of the Main Street Corridor, as city staff has dubbed it, harks back to an earlier commercial order. It was a time when small stores were interspersed through residential neighborhoods. People walked to these businesses to buy groceries, a hammer and nails, newspapers or to have a cup of coffee or a beer. Those days are long gone.

Today, commercial districts must be clearly delineated and have a buffer between them and residential areas. The real estate market is responsible for some of that outcome; large stores need large parking areas and perform better when they are near other retail outlets. But there is precedent in this particular neighborhood for city intervention.

The Shaw’s grocery store on Main Street was built in the mid-1990s. But it was actions taken by the city in 1977 that paved the way for that development. An earlier attempt to improve the neighborhood led to the city buying 3.8 acres and demolishing buildings at the former Gas Works, as the site was known, paid for with a Community Development Block Grant. It was part of the city’s Third Street-Main Street Neighborhood Conservation Project of that time.

So even though the problems of blight and unsafe neighborhoods are somewhat amorphous and subjective, and perhaps respond more dramatically to market forces, government intervention can work.

Code enforcement can be brought to bear on multi-unit apartment buildings. The targeted neighborhoods can get new sidewalks, “pocket” parks and other amenities to then justify higher tax assessments for those run-down properties. When absentee landlords have to pay more in property taxes, they are likely to fix their buildings or sell them.

And zoning is the city’s best weapon. By designating some parts of the corridor commercial and others residential — even if they do not currently reflect that — the city can nudge property owners to take action to improve or sell their buildings.

Changing the character of the corridor will require some money, and the city is wise to pursue grants — federal, state and private — to get the work done. The first essential step is to reach consensus on a vision for the area. Residents from beyond the corridor should take an interest in the discussion, because this slice of Bangor will affect adjacent areas and beyond.