Also, people don't just make choices out of the ether - people's range of choices are influenced by the policy environment. It holds in Sweden too - Swedes didn't make the choice to stay at home until they were given the choice, at which point they did.
At any rate, even if Americans are violently opposed to taking parental leave, surely a non-zero number of men would take it - what's the harm in guaranteeing that men have more chance to bond with their children?