Steel and aluminum are ubiquitous in Americans’ lives. A stainless steel refrigerator holds aluminum soda cans.

Major trade partners swiftly hit back at President Donald Trump’s increased tariffs on aluminum and steel imports, imposing stiff new taxes on U.S. products from textiles and water heaters to beef and bourbon.

The European Commission unveiled retaliation starting in April, Canada announced additional tariffs on US goods and China vowed 'all necessary measures' in response – as Washington edged toward an all-out trade war with allies and competitors alike.