What's behind the US tariffs on Chinese EVs and what do they mean for Biden's re-election chances?

Joe Biden has unveiled US tariffs on an array of Chinese imports, unleashing a potential trade war with Beijing, as the president seeks to woo American voters less than six month out from what's set to be a close election rematch with Donald Trump. The new measures affect $18bn in imports, including steel, aluminium, computer chips solar cells, cranes and medical products - however its the 100% tariff on Chinese-made electric vehicles (EVs) that has dominated headlines. Why have the tariffs been imposed? Biden's national economic adviser, Lael Brainard, perhaps best summed up the purpose of the huge new tariffs…