Trumps threat to put tariffs on car imports is GREAT (For the environment)

The latest kneejerk from the jerk with the knees threatens a 20% tariff on all imported vehicles. Including Mercedes who import un-assembled cars and put them together in the US.. Presumably this legislation will mean that all manufacturers will be paying tariffs on imported components, notably GM and Ford. with more than 20% imported content on average.
The good news for the environment? The only car manufacturer who sources 100% of their content inside the US is... (wait for it) TESLA!!