Of course this a hypothetical scenario but interesting how it could work. If Canadian steel and aluminum is a security threat then maybe pharmaceuticals for Canada could be as well.

Opinion: If Canada wants to decisively threaten maximum pain and stop the escalating trade war with the U.S., it should propose expropriating pharmaceutical patents.

...Thanks to an obscure twist of world trade law, doing so is perfectly legal, too. In the years since NAFTA, developments in international law have made expropriation of pharmaceutical patents easier and less risky than ever. Between 1998 and 2005, at the height of the HIV/AIDS crisis, the World Trade Organization cobbled together special rules making it lawful to “compulsory license”—or, essentially, expropriate—pharmaceutical patents. The rules allow Canada’s government to authorize Canadian companies to copy patented drugs controlled by U.S. companies. There is no need for an AIDS-like health emergency, so long as certain manageable procedural steps are followed. Further, those procedural steps can be shortcut “to remedy a practice determined after … administrative process to be anti-competitive”—likely an easy determination for President Trump’s bogus claim that aluminum and steel tariffs are needed for national security.

Once granted, a compulsory license leaves Canadian firms with the right to copy, sell, and potentially export the targeted drug, at the expense of a U.S. firm who is compensated only pennies on the dollar for the lost value of its patent monopoly. The White House would be left furious by Canada’s decision, but it would be without legal recourse.

There would be several advantages to this move. Macroeconomically, compulsory licensing would mean growth for the Canadian pharmaceutical industry, and decline for the U.S. pharmaceutical industry. Microeconomically, it would mean cheaper drugs for Canadian households, once the American companies’ patent monopoly is broken. From a domestic policy angle, it would mean billions of dollars of savings for Canada’s publicly-funded Medicare system.

And most importantly, diplomatically, it would mean unleashing the most powerful industrial lobby in Washington to beat up the White House on our behalf.