It has played host to countless world leaders and moments in history. Now US President Donald Trump has built a huge cage-fighting arena on the White House’s South Lawn. Cranes lifted giant metal arches into place Tuesday for the Ultimate Fighting Championship (UFC) event on Trump’s 80th birthday on June 14. “We’re having a big fight. It’s never going to happen again, never happened before,” Trump said at an Oval Office event earlier this month, surrounded by four of the fighters taking...