Canada announced it's imposing tariffs on $12.6 billion worth of US products – the same value of the Canadian metal exports affected by US measures (we see what they've done there).
What it means: Canada was particularly annoyed about the US's decision to add extra duties on products imported from them, alongside the EU and Mexico. We're on your side, they said. Why attack your friends?
Now, they're fighting fire with fire, adding tariffs on a bespoke set of products designed to inflict as much damage as possible to industries where Canadian imports are popular with US customers and support US jobs: hence why we've ended up with another oddly specific list of things like sleeping bags, ballpoint pens, playing cards, and strawberry jam.
Meanwhile, the EU has warned that if Trump goes ahead with his threats to impose tariffs on cars imported from abroad, they're really gonna hit back hard. Car manufucturers in the US have expressed serious doubts about the idea too, saying it'd push up the price of vehicles by up to $6,000.
Sum: It's all getting pretty ugly.