The president first announced the doubling of tariffs on aluminum and steel at a rally in Pennsylvania last week.

American steelmakers will most likely be able to charge higher prices as demand for domestic sources of metal increase. But the broader economy is likely to suffer.

US President Donald Trump has signed an order doubling tariffs on steel and aluminium imports from 25% to 50%. The move hikes import taxes on the metals, which are used in everything from cars to canned food, for the second time since March.