Essentially, the market was "freer" before this agreement between Canada and China. China was free to take over some petrol companies in Canada, but we had less direct influence on them. In a free market, no one cares about the sovereignty that one state has.
Similarly, with the U.S., it seems like just as some of our most successful business reach their peak, they are bought out by American companies and that business goes south.
I'm sure we have a FIPA with the U.S., but the free trade aspect still came with obvious detriments like the above.