In effect, we chose to grow our national economy by building infrastructure and increasing interprovincial trade. Since the 1940s, though, Canada has consistently advocated for more liberalized international trade, even while allowing interprovincial trade barriers to persist, or even to increase. Our dependence on international trade makes recent developments on this front very worrisome.
The United States has imposed tariffs on steel and aluminum imports from many countries, which, in turn, have placed countermeasures on a wide range of US products. The United States is engaged in a trade war with China, and extensive measures have been taken on both sides. NAFTA has been renegotiated, but the new agreement still needs to be ratified.