Luxury carmakers Daimler and BMW joined American farmers and Chinese solar panel and steel makers among the first casualties in what looks set to become a bitter trade war on a global scale of a kind not seen since the 1930s.

While most economists believe a tariff war between the world’s two largest economies will not derail global growth even if U.S. President Donald Trump follows through with duties on $450 billion of imports from China, individual industries such as agriculture, autos and technology look set to be hit hard.

Daimler on Wednesday cut its 2018 profit forecast while BMW, whose Spartanburg, South Carolina plant is the largest single exporter of vehicles in the United States, said it was looking at “strategic options” because of the threatened trade war.

The first test of whether a tariff war will indeed start comes on July 6, the date on which Trump has threatened to enact the first portion of duties on a planned $50 billion of imports from China.