[...]

The former parliamentary budget officer Kevin Page projects a contraction in the neighbourhood of the 2009 recession, somewhere between a 2 to 2.5 per cent drop in GDP, along with a ballooning national deficit and debt.

But there's an even bigger story being re-written. It involves Canada's place in the world after 90 years of increased tethering to the U.S. If Trump plows forward he'd be interrupting far more than a few decades of Canada-U.S. free trade; he'd be ending an era that stretches back even longer.

Canada and the United States have steadily built closer economic ties with each other since 1935, as they clawed out of an interminable depression.

These two leaders, Prime Minister Mackenzie King, left, and President Franklin D. Roosevelt, spent a year negotiating the removal of tariffs on hundreds of products during the Great Depression. It set the pattern for generations of trade opening. (National Archives of Canada)