As soon as President Trump proposes and imposes some reciprocal tariffs the UK and EU establishment explodes with rage. They are right that tariffs are taxes on consumers in the country that imposes the tax, with some of the burden shifted to the exporters where consumers cut back or succeed in getting some producer offset to the price hike. So knowing this why do they impose some high tariffs themselves?
They have also failed to confess that they impose plenty of non tariff barriers on trade making imports too dear or banning some of them altogether. The single market is a Customs Union, not a free trade area. It aims to stop foreign competitors by rules and tariffs.
Take beef. The UK still imposes a 12% tariff and £1.47 per kg on beef from outside Europe, but we allow free access for Irish beef. No wonder they clean up on imports, avoiding US competition thanks to tariffs and EU/UK bans on some US production. In many cases our tariffs and regulations are a bigger barrier to imports than US restrictions on our exports to them.
Hitching ourselves to the EU more will be back to our EU experience. It meant dearer food and more imports from the EU. They took most of our fish, banned our beef for a long tine, kept us short of milk quota and gave grants to rip out our orchards.