Hair

Why does Paul spend so much time talking about head coverings and hair?  What is the big deal with hair anyway?  And how short is too short for a woman and how long is too long for a man?  Throughout history the lengths of hair have changed so what is the big deal?
The issue is much bigger than hair length or what we wear on our heads.  The issue is that men are suppose to look like men and women are suppose to look like women.  That has led to many different interpretations of the principle because in different cultures and at different times the dress of men and women will change.  However there is always a distinct difference between the two.
Another reason for talking about hair is that it is a sign of authority or being under authority.  I went to university in the sixties which was the decade of rebellion against the authority.  Men choose long hair as a sign of rebellion.