The tax code is the result of decades of bribery by various moneyed interests who paid presidents, congressmen and senators of both parties to adjust the tax laws to allow them to exempt a wide variety of things, to write down, write off, and pay minimal or no taxes on money made in various ways. For example, in the last tax cut a special tax provision was included which would help... real estate developers. No one seems to be able to explain why.
Which allows scumbag rich boys like Trump to pay a tiny fraction of the taxes ordinary people pay every year.