Parents raising children without interference is great, when the parents don't suck.
There's really two kinds of conscription: military slavery as practiced by Egypt, Russia, Eritrea, for example, and that practiced by western countries to either round out a professional force or develop a functioning reserve. The former is unjust, the latter is part of your duty to your society.
It's also utterly historically justified - we've been conscripting people in the Americas to fight in practically every conflict we've ever fought, from the earliest colonial wars through Vietnam. The last thirty years are an aberration, not the rule.