In recent weeks, a feeling of national unity has surged in Canada in response to Donald Trump’s suggestion that the United States could annex its northern neighbor. Hats emblazoned with “Canada Is Not for Sale” have gone viral, while consumers have begun boycotting American products and canceling future trips to the US.

The threat of impending tariffs has further heightened tension between the two countries, once historic allies. The animosity was on full display earlier this month during the US-Canada hockey match, where American players faced a hostile crowd at Montreal’s Bell Centre. The arena erupted in boos during the US national anthem, and the game descended into chaos with three fights in the first nine seconds.

With an election on the horizon, Canadian politicians have embraced bipartisan unity in response to the diplomatic crisis. Five of Canada’s former prime ministers — Joe Clark, Kim Campbell, Jean Chrétien, Paul Martin and Stephen Harper — recently wrote an open letter asking Canadians to fly their flag for the sixtieth anniversary of the Canadian flag. “We’ve had our share of battles in the past,” they wrote. But we all agree on one thing: Canada, the true north, strong and free, the best country in the world, is worth celebrating and fighting for.”