IOWA CITY, Iowa (Reuters) - Hundreds of people gathered in Iowa City on Friday to watch teenage activist Greta Thunberg speak at a rally to demand that political leaders and institutions take urgent action to combat climate change. Demonstrators, including many young activists, held signs that read “If you breathe the air you should care” and “Science not silence” as they waited for the young Swede to take the stage on the campus of the University of Iowa. “I am more than excited,” said Iowa City resident Philinise Hamlin, 41. “Change doesn’t start until we put our foot forward and...