( CNN ) -- Before memories begin fading of the funny , feisty , combative former mayor of New York City , America would do well to pause one last time , and remember the greatest achievement of the late Ed Koch : his extraordinary , multi-billion-dollar program of building low-cost , affordable housing . It 's easy to lose perspective on the legacy of this larger-than-life character . As host of New York 's only nightly political show , I got to sit and talk with Ed Koch every Tuesday night for the last two years , when he appeared on our `` NY1 Wiseguys '' segment , a weekly forum for retired politicians to weigh in on the issues of the day . Koch 's final appearance came less than three weeks before he died -- and to the very end , he was a dazzling showman , always ready with a quip , a quarrel or a crusade . All of us will miss him terribly . But we should n't miss the main lesson of his mayoralty : Investing in low-cost housing helped families , preserved neighborhoods , and saved a city . And it might be used to do the same for the rest of the country . In 1977 , the year Koch was elected mayor , New York had been devastated by waves of arson , abandonment and economic decline , leaving entire neighborhoods strewn with rubble and vacant shells where apartments once stood . A front-page story in the New York Times captured the scene when President Jimmy Carter made a dramatic , unannounced trip to Charlotte Street in the South Bronx to see `` block after block of burned-out and abandoned buildings , rubble-strewn lots and open fire hydrants . '' Opinion : Koch , a friend and force to the end . Koch , who was elected a month after Carter 's `` sobering '' visit , scrambled to organize a response to the blight but encountered a roadblock a few years later , when the Reagan administration effectively ended federal support for low-income housing , replacing a longstanding program with rent vouchers for the poor . As the federal government got out of the housing business , Koch decided that New York would get in -- and get in big . In 1985 , he announced a $ 4.4 billion plan to create 100,000 units of subsidized housing over a 10-year period , a number that later expanded to 252,000 units that eventually cost $ 5.1 billion . The plan was audacious . It required massive rezoning of the city and coordination between multiple agencies . More importantly , it deployed New York 's capital budget , normally used to pay for sidewalks , roads , bridges and government buildings . Koch put the full faith and credit of the city on the line , borrowing the billions needed for rebuilding and trusting that a general economic recovery would provide the funds to repay bondholders . It was a gutsy move , coming barely a decade after New York 's near-bankruptcy . Tweeters loved Koch 's 'New York-iness ' But the plan was a spectacular success . A veritable army of nonprofit , community-based housing developers worked in partnership with the city to reclaim and rebuild apartments , and neighborhoods like the South Bronx , Bedford-Stuyvesant and Harlem slowly reversed pernicious patterns of decline . Some who had been homeless left the streets and got their lives back on track , while middle-class families moved back in and began paying taxes , raising families and supporting local businesses . Ironically , it was the very neighborhoods Koch saved that provided the votes that speeded his political downfall , with the election of David Dinkins as New York 's first black mayor in 1989 . But Dinkins and every other mayor since Koch has sworn allegiance to the housing plan , using the capital budget and alliances with community organizations to build and subsidize workforce housing . Eulogists remember Koch . It 's surprising that more cities have n't followed Koch 's example . Year after year , for decades , New York has produced or rehabilitated 15,000 units of affordable housing . In some years , it has spent more on housing than the next 50 cities combined . Compare modern Harlem or Bed-Stuy to the most troubled sections of cities like Newark , Baltimore , Philadelphia , and Detroit , and you see what a difference a massive housing program can make . We 'll all miss Ed Koch terribly . It would be a shame to miss a chance to spread his greatest triumph to other cities around the nation . The opinions expressed in this commentary are solely those of Errol Louis .
Errol Louis : Building affordable housing in NYC was a Koch feat ; other cities should follow . He says Koch made major investment in housing to raise up families , neighborhoods . Score: 7 Louis : New York continues to lead in spending on rehabs , new housing , a Koch legacy .