You fail to understand you are supporting this only to hurt others, not to help yourselves at all.  It's like the parable of the two russian serfs - genie offered one serf any wish, but anything he'd grant he would grant double to the serf next door.  So the first serf says 'poke out my eye.'  This is what Trump is saying poke out my eye, so the people of Canada, Mexico and China can have both their eyes poked out!

Protectionism is a zero sum gain.  Trump's ideas will only reduce US GDP and individuals' lifestyle in the long term.  It's why every successful empire has been built on ever expanding trade, not on insularity and protectionism.