The loss of  manufacturing employment  in Canada and the USA is due to corporations  shifting production to low wage/low standard countries. It is not because of automation. This notion about automation and "those jobs would have went anyway"  championed by our political brain trust and promoted by media sources like the Globe and Mail is completely wrong headed. It's denial of the facts. Millions of people are now engaged in making consumer goods,  in subsistence wage countries, that were invented here and formerly made here. It's that simple.
President Trump may be a crude piece of work but he's right about imposing punitive import taxes on companies that have the gall to shift production from the USA to a subsistence wage country and then  import the products back in at the same or higher prices.