OTTAWA — U.S. President Joe Biden's long-anticipated first trip to Ottawa this week is expected to put the state of North America's defences and Canada's military spending back under the microscope. American presidents have a long history of pushing Canada to spend more on its military, including Barack Obama in a speech to Parliament in 2016 and Donald Trump during a NATO summit in 2019. Such pressure has come as Canada has failed to spend two per cent of its national gross domestic product on defence, as agreed by all NATO members, and instead lagged most of its allies on...