Universal military service: how does it work?

Since the whole gun debate over the 2nd Amendment revolves around what the framers meant by a militia, I’ve been reading up on what the Founding Fathers had to say on the subject. I was surprised to read that one framer, Hamilton, and presumably others, never had any intention that military training be universal. The quote is from Federalist Paper No. 29:

So how does a country have universal military training? How do the Swiss, or the Soviets, or the Germans in the 19th century do it? I would guess that the standard was a year of training for just-out-of-school, not-yet-in-the-workforce young men, when they can most be spared. But how does any country that isn’t an armed camp manage to do it?

There’s still a universal military service in Germany.
Since nobody answered, I’m going to tell you briefly how it worked in France. As you assumed all males were called at the ge of 18. Anybody could request a deferment until 21, or even later if they were students. Some people coul be exempted by law (for instance orphans of a father KIA, or people whose presence was indispensable to run a family business) but there weren’t many of them. Some alternate forms of serviceexisted (for instance for consciencious objectors). Everybody passed tests ad a medical exam, and a minority was exempted (not to be called except in time of war) or rejected at this stage.

The military service lasted for one year (but until the beginning of the 20th century, it was two years, IIRC), longer for people requiring a special formation (for instance joining a paratroop unit or a reserve officer school, on a voluntary basis). The mandatoy service lasted for one year, the first months in training and then in an actual military unit. After that, people were in the reserves for ten or fifteen years, and could be called back for periods of training at any time during these years. This was not on a volountary basis. It was rather uncommon, but if it happend to you once, you could bet you’d be called back again and again…

The draftees could be promoted to the lowers NCO ranks or selected and trained as junior officers, so part of the NCO/officers of the non professionnal military units were themselves undertaking their military service.

Draftees were normally never sent in warzones, or in foreign operation theaters (except in time of war, but last case had been the Algeria war in the 50’s), except when they volunteered, or had chosen to join an otherwise professional unit (and of course, since that’s the miltary we’re talking about, when they wanted them there anyway for some reason, even though it shouldn’t have happened. I personally know of only one such case, though.)

As for the whole coutry being a large military camp, well, maybe in a way. But remember that there used to be this “cold war” thing (and before that a war could break up at any time, see WWII and WWI etc, etc…) Continental european countries needed cannonfodder, trained and available immediatly. The potential ennemy, be it the austro-hungarian empire or the soviet union wasn’t going to wait for six months after the declaration of war until your own troops would be trained. A signifiant part of the french draftees were actually stationned in Germany, waiting for the day when the soviet tanks would rush in, for instance. Most others were in a limited number of garrison towns or cities, so in some places you would see soldiers everywhere, but hardly ever any in most towns.
As far as I know, the system is quite similar in Germany, except for the fact that nowadays a lot of the draftees undertake some form of alternate civil service instead of the mandatory military service.

On the other hand, the system in Switzerland is very different. Men are basically all reservists and must attend training sessions on a regularily scheduled basis, and during many years. I don’t know the details.