President Trump's steep steel and aluminum tariffs are official. The goal is to protect domestic industry by propping up American steel and aluminum manufacturers. Trump is using a little-known trade law to claim that steel and aluminum imports pose a threat to national security. China has threatened to be tough in response to steel and aluminum tariffs in the past. The European Union said earlier this week it would file a complaint with the WTO, which will then need to determine whether the Trump tariffs violate its rules.

Source: CNN March 09, 2018 00:11 UTC