"How come 'national service' proponents never talk about drafting the old?"

Great question, by Ilya Somin.

[T]he moral case for conscripting the elderly for civilian service is arguably stronger than that for drafting the young. Many elderly people are healthy enough to perform nonstrenuous forms of "national service." Unlike the young, the elderly usually won't have to postpone careers, marriage and educational opportunities to fulfill their forced-labor obligations. Moreover, the elderly, to a far greater extent than the young, are beneficiaries of massive government redistributive programs, such as Social Security and Medicare--programs that transfer enormous amounts of wealth from other age groups to themselves. Nonelderly poor people who receive welfare benefits are required to work (or at least be looking for work) under the 1996 welfare reform law; it stands to reason that the elderly (most of whom are far from poor) can be required to work for the vastly larger government benefits that they receive.

Great issue! Somin thinks politicians focus on the young is that they don't vote. Old people do, and they'll blow a gasket if anyone tries to push them around. (And, lest you rile them, you'd better pay for all the drugs they see fit to take.)

Another thing is that young people are assumed to need training to fit into an orderly and good society. They tend to be in a state of flux, footloose, and full of dangerous passions. We old people are scared -- and jealous. So even as we're devising schemes to make our lives a bed of ease, we're thinking up new ways to control you. How lovely it is when you serve us.