Donald Trump’s plan to impose 50% tariffs on Canadian goods from 1 January has alarmed leaders across the Detroit-Windsor region, where about $1 billion in goods crosses the border each day. The proposed duties would cover products ranging from automobiles and honey to hockey sticks, and Canada has announced retaliatory tariffs on $20 billion of goods. Michigan voters oppose tariffs on Canadian goods by 63%-31%, including 35% of Republicans, while nearly 75% say tariffs are fueling high prices, according to a June Epic-MRA poll. The issue could affect the 3 November general election, as Democratic nominee Abdul El-Sayed challenges Trump ally Mike Rogers in a race central to Democrats’ hopes of retaking the Senate. Michigan has selected the presidential winner in five consecutive elections. The United Auto Workers, which has 350,000 members in Michigan, rejected the latest escalation, while economists warn that both economies would suffer. North America’s auto industry is deeply integrated, with parts crossing an international border an average of six times before reaching a finished vehicle. The dispute has also cooled investment in Windsor and prompted criticism from the Detroit chamber of commerce, which said escalating tariffs would cause economic pain on both sides of the border and benefit global competitors such as China.