I thought he was a pro business pro trade traditional Republican?  Blows my mind that this bitter protectionist border tax would come from his camp - esp given he is from a border state (WI) where fully 1/3 of Wisconsin state exports are to Canada, IIRC.  Some more facts: Wisconsin exports 7.3 Bn/yr to Canada and imports only 4.2 Bn/yr from Canada!  Seems his own state would be hurt if US put up a 20% border tax against us, and we retaliated in kind.