Oh really?

Country A has no tariffs on the goods it imports.

They are trading with country B.

To protect it’s own domestic orange growing industry they pass a 50% tariff on the Oranges they import from A.

Fair trade has just ended because there is no longer free trade.

A then reciprocates with a 50% tariff on all goods imported from B and says it will remain in place until B drops the tariff on oranges.

B drops the tariff, we now have a level playing field and A drops it’s tariffs as well.

We now have fair and free trade between A and B.