"If we're going to ask every American to serve,
every American should serve." — Hon. John McCain
US Senator, interview 22 October 2017,
quoted on Huffington Post
I recall Senator Ted Kennedy's staff running the numbers a few decades back and concluding that even demanding a year of service from every American at 18 or 19 would be prohibitively expensive. Still, I like the principle Senator McCain has presented, and I'll repeat my suggestion for an affordable and equitable compromise:
Take almost literally, and implement, the official American doctrine of "Universal (military) obligation and selective service."
As long as we require 18-year old male residents of the US to register for the Draft, it's probably safer for liberty to both expand and contract the pool to all American citizens 18 to 80, with everyone filling out a brief form with our physical and mental condition, skills, and current contact information. As future cohorts turn 18, they can register in more detail, including some testing, ending with a little ceremony at which they receive a card that can serve as short-form passport and for voter-ID/registration, and registration as Of Age for the purchase of alcohol and any other legal recreational drugs.
"Old enough to fight, old enough to vote; old enough to vote, old enough to 'drink' (i.e., ethyl alcohol as a recreational drug)." A rite of passage for Coming of Age in America would be useful to help cure the current American epidemic of arrested development.
Everyone in a computerized system makes real "Universal obligation," with the provision that "the System" be programed to call up people for service as needed, with the political tweak that two members of Congress and a US Senator will be called up each month of a military draft: If they got us into this emergency and perhaps declared the war, let's be sure at least some of them fight it.
(Last time I made this suggestion, I had to consider what possible contribution to some war effort could be made by Senator Strom Thurmond, who was approaching 100 years old at the time. I noted that the System could be set up to allow for extreme age in members of the Congress and to give credit for previous military service, especially such superior service as that of Thurmond — no, World War II, not the Spanish-American — and, besides, in Thurmond's case there was always mine clearance …. More seriously, by "service" I meant Federal Service, in the sense used by Robert A. Heinlein in the more carefully considered, and perhaps even revised, sections of his Starship Troopers : maybe militaristic, in the novel, but not necessrily military. For Representatives and Senators, though: military if at all possible. There're always military jobs as guinea pigs at Fort Detrick.)
Other advantages to Universal Obligation: Senator Sam Ervin opposed military conscription for women with a line something like «America is not ready to see her daughters coming home in aluminium coffins.» That has turned out not to be literally the case so far, so long as the coffins are few; and insofar as it is the case, it's an argument for drafting women. American society can use every check we can get on war fever, and if a squishy sentimentality over the deaths of young women reduces the number of deaths, period, then go for it. Also, the US Left and Center have clearly been way too optimistic about the progress of women toward full integration into American political and civic society. Military service has helped other groups into US society; it should also help women.