Maybe churches can't be forced to conduct them now. But some day, a gay couple is going to demand that the Catholic diocese in some ultra-liberal part of the country allow them to receive the Sacrament of Marriage from a priest in a traditional Church ceremony. The Church will refuse, the gay couple will go crying to the media, and the liberal state legislature, anxious to prove their tolerance and their political correctness, will vote to revoke the diocese's tax-exempt status until they become more "progressive" in their thinking.
The inevitable lawsuit will make its way to the US Supreme Court over the course of a couple years, and all during this time there will be constant media attacks on the Church, with lots of push polls being taken that "demonstrate" that the American people overwhelmingly support making the Church perform gay marriages. Over the couse of this time, many of the more liberal churches will have caved to the threat and will have allowed themselves to be intimidated into abandoning their Scriptures and doctrine.
The Supreme Court will inevitably rule that the state has a "compelling interest" in guaranteeing fair treatment to all citizens that overrides the Church's Constitutional protections under the First Amendment. This is a given, because to liberals, "freedom of religion" is a one-way street - it means that all aspects of religion are to be banished from public life, unless it's expedient for liberals to invoke them (as in the case of gay marriage). But the government, of course, has no limits in telling churches how to run their affairs and establish their doctrine.
"But some day, a gay couple is going to demand that the Catholic diocese in some ultra-liberal part of the country allow them to receive the Sacrament of Marriage from a priest in a traditional Church ceremony. The Church will refuse, the gay couple will go crying to the media, and the liberal state legislature, anxious to prove their tolerance and their political correctness, will vote to revoke the diocese's tax-exempt status until they become more "progressive" in their thinking."
Faith endures, even beyond the loss of its tax exempt status. I imagine that others before us may have faced greater suffering and pain in the name of Jesus.
Let the government collect its pieces of silver.