In time, Millennials (like the Gen X'ers of the '90s, or Boomer hippies) will mature and realize that a sluggish economy and high taxes are in fact impeding their social causes as well. And that what they really care about now is paying their bills, a reasonable standard of living, and planning for retirement.  They'll also learn that while government cannot control much of this (despite any promises), certain governments (a la Trudeau) can be an impediment.  Might seem counterintuitive now, but a socialist government may be hurting some of their causes.