Now we agree. We do have different world views. I am not sure what your world view is based upon. But, mine is based on practically what works and what is natural. Monogamy is UNNATURAL. It is a recent construct by a religious few. I am not with my ex-wife. She is remarried and I am about to be. Our children are thriving, healthy, and will be productive. To say only biological parents should be responsible for children negates 90% of the people in a childs life. So, again we agree...we have different world views that each work for us. The question is, what will work best and most practically for our communities.You and I have different world views. I understand this and am perfectly ok with it. In my world view, "stepping up" means that the man does not conceive a child with a woman that he has not made a lifetime commitment to and he does not change that commitment when it becomes convienient or he "just doesn't want to be with the woman anymore".
My view of responsibility is simple. It takes a man AND a woman to conceive a child, it also takes that same man and woman to provide the optimum environment and nurturing for the life of that child. Creating a child outside of that mindset is irresponsible.
You may think that idealogy is too simplistic for this "complicated" world, but I submit that things only get complicated when idealogies are convoluted.
My world view works for me. One man and one woman, join together under God until death do they part. I understand that every man does not subscribe to this ideology. Therein lies the problem.
Peace and love