Begs the question, can you be left wing or centre left if you approve of 0 tarrifs?
I think you have to understand why we have tariffs at customs. to protect our home market, one of the first things a UK trade negotiator should do is work out what goods etc do we need to protect and come to a agreement to protect them with tariffs and quotas otherwise cheaper countries exploiting their workforce will undercut us, one of the best examples is Oranges. nobody grows Oranges in this country therefore we have no problem allowing Oranges to be imported tariff free which they are. a picture of a big supermarket fruit stall was going around the internet last year in response to the ERGs claim of being able to have zero tariffs on certain fruits etc, the photo pointed to nearly every fruit imported, everything was already coming in tariff free as we can't grow these fruits in this country anyway.
I can only go on what Corbyn said one Sunday morning last year.
Shocked me. He argued EU tariffs are protectionist. they drive down wages in poorer countries outside the EU as bosses are forced to pay lower wages to compete,!!!!
Theres so much wrong with his argument, he is thinking more about the poor in other countries than the people of this country, he assumes bosses outside the EU who exploit their workforce will pass on the savings from no tariffs. he is arguing a trickle down economy in poorer countries.