During the last Democratic debate, in Ohio, there was a moment that stood out. Elizabeth Warren and I got into a debate over the impact of automation versus trade on the elimination of manufacturing jobs. Joe Biden also chimed in, agreeing that the fourth industrial revolution is costing jobs, so it’s important to deal with the root causes.

Immediately, fact checkers were quick to point to a study showing that 88 percent of factory job losses from 2000 to 2010 were caused by automation. Yet, in the days following that debate, some prominent media figures asserted that the threat of automation is not real. The Times columnist Paul Krugman even called it “a sort of escapist fantasy for centrists who don’t want to confront truly hard questions.”

It’s easy to cite incomplete statistics that ignore the full picture and the situation on the ground, but I’ve done the math while spending time in struggling communities. Venture for America, the nonprofit I founded, sent me across this country, to Detroit, St. Louis, Birmingham, Ala., and other communities, where we attempted to spur entrepreneurship and create jobs. It was during this time when I spoke with workers who had lost their jobs to automation and couldn’t find more work. My organization was helping to create jobs, but automation was displacing tens of thousands of workers in these states. We were pouring water into a bathtub with a giant hole ripped in the bottom.

On the campaign trail, I’ve spoken with workers in Michigan, Ohio and western Pennsylvania, workers who are worried about the inevitability of their jobs falling victim to automation.