The US-Canada aluminum fight is escalating, and both countries' aluminum industries say the tariffs are hurting them more than they help.

• Washington keeps a 50% tariff on Canadian aluminum, and Ottawa has hit back with a 50% tariff of its own.
• Aluminum industry groups on both sides want the fighting to stop and a shared wall built against cheap Chinese metal instead.
• The US buys most of its raw aluminum from abroad, with Canada as the biggest supplier, so it cannot go it alone even if it builds new smelters.
• Trump's tariff created winners and losers at home: US metal producers gain, while companies like foil makers eat higher costs and pass them to shoppers.
• Constantly shifting trade rules are making producers reluctant to spend on new plants, which undercuts the goal of rebuilding US manufacturing.

Outlook: Washington will likely have to give ground in trade talks with Canada and Mexico to reach a regional deal.