Is that a consequence of US or Canadian policy?

Its a consequence of being the only close country. Generally trade is easiest with countries that are nearby. NAFTA helped a lot too.

Every Canadian province except PEI trades more with the US and with the rest of Canada.

When Trump was elected the first time, super genius Canadians vowed to fight his trade policy by targeting American politicians in states that trade with Canada, threatening to cut them off. The only problem with that is that Canada is far more dependent on trade with the US than US states are with Canada. <https://np.reddit.com/r/MapPorn/comments/8q9h8i/canadaus_tra...>

“Outside of NAFTA”

Are the softwood lumber tarrifs part of nafta? The steel tarrifs?