Trump’s threat came days after he warned Canada of a 100 per cent tariff if Ottawa proceeded with a trade agreement with China. Why has Trump threatened Canadian aircraft with 50% tariff? He warned that the US would decertify all Canadian aircraft, including planes from its largest aircraft maker, Bombardier. Referring to Carney as "Governor," Trump said the United States would impose a 100 per cent tariff on Canadian goods should Canada deepen trade ties with China. Trump responded by saying Canada "lives because of the United States" and should be grateful, prompting Carney to fire back that "Canada thrives because we are Canadian.