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Welcome to the History Extra podcast, fascinating historical conversations from the makers of BBC History magazine.

From US tariffs on imports to threats of retaliatory action from other nations, there's been a lot of talk about trade wars in recent weeks.

But can history offer up anything

to enlighten the current situation? Matt Elton caught up with Frank Trentman, Professor of History

at Birkbeck University of London, to find out. Frank, thank you so much for being with me today

to talk about tariffs and trade wars, subjects that have been in the headlines

a lot recently. It's a fast-moving situation. We're not here to talk about the current affairs

side of it, but to look back at some of the history of this. What do you think is the earliest

historical example that comes to mind when you've been reading these headlines?

Well, states have always tried to control what goes in and out of their country,

but it's perhaps worth mentioning in the current context that actually the tariff is the first ever

act of Congress passed by the United States.

...