OTTAWA—Tighter border controls will come into effect Feb. 22, the prime minister said Friday, not to punish travellers but to try to keep everyone safe. Forcing new arrivals into a mandatory three-day hotel quarantine—at their own expense—and requiring a COVID-19 test when they get here is meant to help ward off new and more transmissible variants of COVID-19, Prime Minister Justin Trudeau said. Nobody wants a third wave to start, Trudeau said at a news conference outside his Rideau Cottage home. “Our goal is not to punish people,” he said in French. “Our goal is to protect and to discourage any non-essential travel.” The government had announced the plan for the new border controls last month but how they will work, who might be exempted and how they will be enforced was laid out Friday. All those coming into Canada for non-essential reasons were already required to quarantine for 14 …