Steel, aluminum tariffs take effect, drawing retaliation from U.S. trade partners

After a rapid-fire series of escalation threats and exemption requests, President Trump has allowed stricter 25 percent tariffs on imported steel and aluminum to take effect without changes, prompting a new wave of retaliation from trading partners -- with Canada and the European Union the first to announce their plans. The White House announced no exemptions, stays, or other mitigating moves for national security duties under Section 232 of the Trade Expansion Act of 1962 that Trump set in motion...