What are reciprocal tariffs, and why does Trump want to impose them on other countries?

A core element of the protectionist trade policies President Trump is scheduled to announce on Wednesday — a planned import tax blitz he has referred to as "Liberation Day" — are so-called reciprocal tariffs. Mr. Trump has touted such levies as a way to level the playing field with other countries that impose higher tariffs on U.S. imports, as well as to boost domestic manufacturers. 

But some economists say that tit-for-tat tariffs with key trading partners could be hard to structure, while also roiling global commerce and driving up costs for U.S. consumers and businesses. Here's what to know about reciprocal tariffs.