The office of the U.S. Trade Representative says it will lift the tariffs retroactive to Sept. 1 because it expects Canadian exports to “normalize” over the remainder of the year.

When USMCA took effect July 1 with no new tariffs on the three trading partners, some uncertainty and tension eased, and the auto industry exhaled. The relief was short-lived.

The U.S. president originally imposed the tariffs on aluminum imports in 2018. He then lifted them last year on Canadian and Mexican metals to smooth the way for the US-Mexico-Canada Agreement.

The replacement for NAFTA presents new rules and little time to adapt, complicated by the economic turmoil created by the pandemic.