If a civilian gets caught doing something illegal, they are entitled to a fair trial with a jury of their peers. If a military member gets caught doing the same thing, the court martial is a mere formality, they just more or less go straight to jail for a very long time.
This topic has been litigated a lot in front of SCOTUS like with Standard Form 86 (where one waives the right to free speech for security clearance) so there’s certain language they have to contain to be valid.
Courts have upheld this because Congress has the power to regulate the military, but it still feels like a huge shift in rights for someone forced to serve.
It feels... intuitively unjust that the government could compel service and then subject individuals to a system that limits their constitutional rights.
and unfair, considering that rich people always found ways to dodge the draft or serve in armchair positions, but taking this into account it's just even more obvious that special interests did what they usually do.
So ostensibly a draft occurs when the country is facing a threat to its existence. So if you feel bad about the concept of a draft, understand that the alternative may be a lost war.