This has been a cornerstone of his campaigns since the beginning. I don't necessarily believe they understand the details, but I do believe they understood he would impose high tariffs, and still voted for him anyway. Tariffs weren't a throwaway line, or something. He repeated it everywhere he could.

I think it is true that most people don't understand the economic principles of tariffs, including most economists. But I do think the plan he's implemented largely comports with what he's consistently said he would do.