>Tariffs have existed in every country capable of enforcing them for all of human history, and they existed in the US prior to Trump, and will continue to exist after Trump. Even countries we have supposed "free trade" agreements with still get tariffed (and impose tariffs on our goods).
To what degree relative to what we're seeing now, though?
Much, much more than what we're seeing now, historically. Including outright banning all or nearly all foreign trade. See Japan under the Tokugawa Shogunate for one of the more extreme examples.
To what degree relative to what we're seeing now, though?