CEDAR RAPIDS — As America experiences the greatest economic transformation in its history, it’s up to Iowa to make sure no one is left behind.America is in its fourth industrial revolution as “technology is advancing to the point where fewer and fewer of us will have the same level of economic value,” according to Andrew Yang.The former technology entrepreneur, who is seeking the 2020 Democratic presidential nomination, is warning that automation and artificial intelligence will displace millions of American workers — from retail clerks to truck drivers — and disrupt not only the economy but society as a whole.“So we have to get our heads up and evolve in the way we think about ourselves and our own value,” Yang, 44, told students and community members Wednesday at Kennedy High School in Cedar Rapids.Fortunately, he said, Iowans hold the power to make that happen.“You all are very powerful individuals,” Yang said, explaining that because of Iowa’s first-in-the-nation precinct caucuses, each Iowan has the power of 1,000 California voters.