Donald Trump enters the White House on Friday just as he entered the race for president: defiant, unfiltered, unbound by tradition and utterly confident in his chosen course. In the 10 weeks since his surprise election as the nation’s 45th president, Trump has violated decades of established diplomatic protocol, sent shockwaves through business boardrooms, tested long-standing ethics rules and continued his combative style of replying to any slight with a personal attack – on Twitter and in person.