Labor Participation Crisis- Men Fleeing Work

Over six million prime-age men are neither working nor looking for work; America's low unemployment rate hides the fact that many men have dropped out of the workforce altogether. Our workforce participation rate is on par with that seen during the Great Depression.

Why does this problem affect men so acutely? Why is it so specific to America? What are these missing men doing with their time? How do we differentiate between leisure and idleness?