Bertrand is an avid supporter of protectionism. His primary political principle is the idea that the United States imports too many foreign goods. He dislikes that many of his clothes are made in China instead of the United States because clothing is a basic need, even for babies. He would prefer that the United States drill in the Arctic National Wildlife Refuge (ANWR) instead of importing oil from Kuwait because oil powers our military's tanks and planes.

Which argument for protectionism is bertrand using?

Protectionism is a term used in economics which describes a country protecting it's industries from interference by import/exports and taxes from other countries so that they can continue to operate in the case of a war and provide a sustainable environment during that time for the people.

Protectionism has 6 arguments and the example given by Bertrand in the question is "The National Security Argument" which is the protection of certain industries and providing that they can continue to produce crucial things, without the help of other parties, such as petrol, clothing and food if there is a war.

I hope this answer helps.