Can somebody explain to me on what authority the US can request the arrest of a Chinese national on Canadian soil for any action they took while conducting operations of a Chinese organization headquartered in China?
Did you read the article? US is alleging Huawei was shipping "U.S.-origin" products to Iran - probably U.S. made components for Huawei devices/technology. What "authority" do you need to ask for a favor from a friendly ally? Canada also has active economic sanctions against Iran.
What if the us origin component was a plastic bezel, a screw or some peice of sheet metal in the chassis...