—“Only half participate in the work force? Really?”—
um… that’s normal. children, stay at home moms, and the elderly. 20 years to mature, 40 years of work, 20 years of retirement = 50% employment in an evenly rotating population.
That simple sentence is enough to explain why redistribution doesn’t work. Costly to train, costly to reproduce the next generation and work, and costly to support in old age. Basically if you can’t pay for yourself you’re screwed.