Donald Trump is threatening to use “economic force” to make Canada the 51st American state. While his comments may be reckless, they are in part due to Canada’s over-reliance on the US market in terms of trade. The benefits of international trade are undoubtedly positive. It’s well-established that when countries can produce a product or service more cheaply than others, giving them what’s known as a “comparative advantage,” all other nations engaged will gain from that trade. …But the key challenge Canadian policymakers face is an over-reliance on the US as Canada’s primary market, with 75% of all Canadian exports headed south. …Canada can no longer take easy access to the U.S. market for granted. …Bringing down barriers to trade across Canadian provinces would create conditions that could enable Canadian companies to be more competitive internationally, and beyond the U.S. market in particular.