“Traditional marriage was not upheld, was not valued by the parents of the last generation or two. If you want to know how it came to this look in the mirror. Look to your left, look to your right. That’s how.”
“Now, since the family and human society at large spring from marriage, these men will on no account allow matrimony to be the subject of the jurisdiction of the Church. Nay, they endeavor to deprive it of all holiness, and so bring it within the contracted sphere of those rights which, having been instituted by man, are ruled and administered by the civil jurisprudence of the community. Wherefore it necessarily follows that they attribute all power over marriage to civil rulers, and allow none whatever to the Church; and, when the Church exercises any such power, they think that she acts either by favor of the civil authority or to its injury. Now is the time, they say, for the heads of the State to vindicate their rights unflinchingly, and to do their best to settle all that relates to marriage according as to them seems good.”
Pope Leo XIII, 1880
He saw it coming 130 years ago, that many would be conditioned to think the state defines marriage, and how the statists would use that.
Freegards
Foreigners have their views, but if he were American he would know that the US government had already moved against church imposed polygamy.
Why wouldn't he know about Italian laws on marriage, he was Italian and should have known his country's laws before he was pope.
He should also have known about Roman marriage laws and ancient Greece and laws about marriage.