If they make you cut short hair, and you follow, it's actually a
form of obedience.
You don't follow, it's rebellion.
There is no practical reason for short hair in schools, it's not
hot especially when you sit in lectures all day.
They ask you to cut, because they can.
As for the army, it's a military trend.
Of course it's less hot and obstructive.
So it's ok.
