WASHINGTON — The man in charge of protecting Canadians from malicious hackers says it is vital for Canada and the United States to keep working closely together on cybersecurity. Sami Khoury, the head of the Canadian Centre for Cyber Security, was in D.C. this week for an international cybersecurity summit and meetings with U.S. counterparts. Khoury says the two countries have become essential partners in fortifying the continent's cyber defences, a collaboration he expects will only continue to grow. But in a world of ransomware, foreign interference and hostile nation-states, he worries that citizens and businesses alike aren't taking the...