Former Florida Governor Jeb Bush is calling on President Donald Trump to end the “heartless” policy of separating immigrant children from their parents at the U.S. border. “Children shouldn’t be used as a negotiating tool,” Bush tweeted on Monday. “@realDonaldTrump should end this heartless policy and Congress should get an immigration deal done that provides for asylum reform, border security and a path to citizenship for Dreamers.” The failed presidential candidate’s plea came in response to President Trump’s tweet in which he vowed to stop “some of the worst criminals on earth,” from using children to illegally enter the U.S....