Try to fight a war with lawyer and not a factory worker.
Easy - put the lawyers in the front line like Soviet penal battalions and let them soak up the enemy’s fire.
The art of warfare has become so complex these days that conscription is basically just creating cannon fodder. Modern warfare of the kind practiced by the West requires trained professionals. Even the basic rudiments these days requires at least 14 weeks of instruction and it’s another several months before recruits start really getting proficiency.
Another factor is automation. We simply need less people to turn out a good these days with automation.
Try to fight a war with lawyer and not a factory worker.
Plus, too many idiots would happily outsource our Defense work...to China! After all, many Defense workers are conservative, so by all means, put them out of work.