Your statement is a little inaccurate. Unless it is rape (i.e. no consent), they both are responsible for the pregnancy. I think men are tuning out because regardless of the fate of abortion rights, men don't have any rights post conception. If the woman wants to keep the child, the man is forced into parenthood. If the woman doesn't want to keep the child, the man has no say in that either. The woman can even decide to have the child and give it up for adoption without telling the man. Men have no reproductive rights. So for many of us, it's hard to feel an attachment to women's rights post conception.