Our writers offer key context as Hillary Clinton and Donald Trump make their case for the White House
US President Barack Obama (C-L) and Prime Minister of Canada Justin Trudeau (C-R) watch the Fife and Drum Corps perform at an arrival ceremony on the South Lawn of the White House, in Washington, DC, USA, 10 March 2016. This is the first official visit of Prime Minister of Canada Justin Trudeau to the White House. (Michael Reynolds/EPA/CP)