Affirmative Action, Equal Rights, but when are Fathers going to have equal rights at seeing their children?

When a father leaves his ex partner or wife, he pretty much gives up any rights to his children if the mother wants to play dirty. Why is it not a constitutional and natural right for a man to be involved in the lives of his children without having to pay a lawyer and fight for it. NO man should have to fight for equal parenting time, spending thousands and missing time with his children. A shared b50/50 should be automatic, NATION WIDE, for any father who wants it as long as the parents are deemed fit. Many states have already adapted this automatic Shared Parenting, but it should be Federally mandated. PLEASE FIGHT THIS FIGHT FOR THOSE WHO CANNOT!!!!!!E