In 2012, when Mark Carney left Canada to helm the Bank of England, he said he was going to where “the challenges are greatest.” Those now facing him as Canada’s prime minister are significant. The five-week campaign and electoral map revealed a country with two dominant parties with starkly different agendas — and regional divisions that could test national unity as Canada confronts President Donald Trump’s trade war and annexation threats.

New Canadian Prime Minister MARK CARNEY may have U.S. President DONALD TRUMP partly to thank for his Liberal party’s resurrection and historic electoral win. But on his first day in office, he already faces a bevy of national security headaches centered on the Trump-fueled breakdown of U.S.-Canada ties.

Canada’s Prime Minister Mark Carney has been an international leader on climate. Can he translate that into domestic policy?