He's not talking about taxation. He's saying, "Before you institute a draft and force healthy young men into poverty, suffering, mental disorders and death, for

He's not talking about taxation. He's saying, "Before you institute a draft and force healthy young men into poverty, suffering, mental disorders and death, force the people who profit from such action into exactly the same situation (e.g. max salary of whatever the soldier's max salary is, production at bare costs, etc)." He's making the point that war would suddenly cease to be an option, because only the poor and powerless can be conscripted. If you started conscripting everyone in the same way, the rich and powerful would stop any such war from occurring in order to avoid such pains.