I’m not sure, but they are more explicitly implemented through tariffs than in Europe. 

Undisciplined

the IMF estimates that remaining barriers to trade within the countries of the EU are equivalent to a 44% tariff on trade in goods, and a 110% tariff on trade in services.

econ

EU offers Trump 'zero-for-zero' tariffs deal on all industrial goods

Coinsreporter

I see. 
> the IMF estimates that remaining barriers to trade within the countries of the EU are equivalent to a 44% tariff on trade in goods, and a 110% tariff on trade in services.

 I wonder how much trade barriers US has? 