It is also boils down to fairness. Because children can't choose their parents. So either society take a responsibility for children or you end up with a socitey their who can start a sucessful business or ends up on the street is a lot based on badluck.
That having children is a very strong basic human instict, and that is because that we are all here. That we have all ancestors that didn't afford to have children and still had them. So if poverty and terrible life would stop people from having children no one of us would be here.
But today both my country Sweden and USA is rich to give ever child a change of a good life. Also how can how can you talk about personal responsibility to fail and sucessed if a childs destinity is so much based on the parents it is lucky to have?
That even if you dislike welfare you may see that you need welfare for children for a fair society.