Ummm... there are some things which are just good for society. Having children is one of them. "Everyone else paying for it" is a reasonable thing, especially in this day and age when people don't want the hassle of having kids.
You're presenting an extremely selfish point of view.
By the same token, I've never understood how parents could advocate against having a one-income family.
Oh wait, I know. Because everything has a cost, and everything is a trade-off.
The reason to not have a year-long leave is the same reason not to have a stay-at-home parent: it's expensive.
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Of course, some people do wind up making that compromise. But Americans don't expect everyone else pay for their decision. Thank God.