Union Membership and the Middle Class

There is a direct correlation between union membership and the decline of the middle-class.
Without labor making demands to drive the economy- by increasing consumer buying-power  and fighting for fair health insurance & pensions, an ever-larger portion worker's wages are going towards funding their own benefits that used to be employer-paid, and they're doing it with stagnated wages that haven't kept up with inflation.
Failed Trickle-Down economic theories and attacks against labor unions has driven income disparity to that not last seen since the 1929 Depression.