This time the US government picked a fight with the people though, those are the ones who need to bear the brunt of those pointless tarrifs.

Did Europe not have tariffs before Trump?

But in this case the fight got picked by "the US", as europeans it's about "self defence", so the will to join the boycott may be greater.

Social media makes it possible for leaders of nations to pick fights with random individuals on Twitter. Or entire subcultures, nations, or groups of people.