Cities such as San Francisco and Chicago are trying to save their downtown office districts from spiraling into a doom loop. St. Louis is already trapped in one, with abandoned buildings, vacant offices and shuttered shops and restaurants. WSJ’s Konrad Putzier unpacks the lessons from downtown St. Louis’s doom loop. Further Reading: -The Real Estate Nightmare Unfolding in Downtown St. Louis  -Commercial Real-Estate Woes Run Deeper Than in Past Downturns  -Can San Francisco Save Itself From the Doom Loop?  Further Listening: -The Downfall of a Real Estate Empire  -What’s Keeping Zombie Malls Alive?  Learn more about your ad choices. Visit megaphone.fm/adchoices