June's Obergefell v. Hodges ruling, which mandated recognition of same-sex marriages across the United States, was largely recognized by both supporters and opponents as a groundbreaking ruling.

What are the factors that led to this wide-reaching Supreme Court decision? And what will happen next in the marriage landscape?

Ryan T. Anderson, an author and Senior Research Fellow at the Heritage Foundation, seeks to answer those questions. He traces what he sees an erosion of marriage over the past half-century – as well as examine the future of marriage in the U.S. – in his latest book, Truth Overruled: the Future of Marriage and Religious Freedom.

Anderson begins by saying that the overall restructuring of marriage began long before legalizing homosexual marriage was even a discussion.  

"It's not gays and lesbians who were the first to come up with the idea that 'love makes a family,'" Anderson told CNA, saying the slogan came out of the '60s and the birth of the sexual revolution, which backed the notion that marriage lasts only as long as the feeling of love does.

"In general, the values that come out of the sexual revolution are saying that consenting adults can do whatever consenting adults want to - the only value that matters is consent," he continued, saying this sentiment is an all-too-familiar quality that has carried itself into the modern-day discussion of marriage.

Post-sexual revolution, America saw the steady rise of the hookup culture, non-marital childbearing, divorce, and cohabitation, he said. This escalation ignored the traditional, comprehensive understanding of marriage as a life-long, permanent bond between a man and a woman - making it more and more feasible to redefine its meaning.

"It's only after a generation or two of heterosexuals making a mess of marriage that it is even plausible to have justices legally redefine what marriage is," Anderson asserted.

Allowing same-sex marriage across the country is not the only problem with the Obergefell v. Hodges ruling, according to Anderson, who says this decision also tackles an additional political hurdle.

"The U.S. Constitution does not define marriage one way or the other - they leave that up to the states," he said, and it is "unclear" why five Supreme Court justices were given the ability to make the decision for all 50 states when the Constitution remains silent on the matter.

Ever since the ruling in June, Anderson said, religious freedom and democratic justice have been threatened by the very fact that the tradition of democracy was usurped during the proceedings of the 5-4 ruling.

"The Supreme Court's ruling is not just going to impact marriage, but also civil society, religious freedom, education, our children and grandchildren," he wrote.

First, "redefining marriage teaches that men and women are interchangeable, that moms and dads are replaceable," stated Anderson.

"It makes it further difficult for us to say that fathers are essential, whereas redefining marriage makes them optional," he continued, saying that every family with a mother and father have been undermined by this decision, cheapening the very fabric of familial culture.

Secondly, Anderson says that the ruling paves the way for polygamy, which is currently illegal in all 50 states.

"Once you get rid of the male-female part of marriage, there is no reason for marriage to be monogamous, exclusive, or permanent," he said.

The author also pointed to other effects of same-sex marriage on Americans, such as the Colorado cake baker who is facing a lawsuit for declining to bake a cake for a same-sex ceremony. Anderson said, this is just one example of how individuals and religious freedom are being manipulated in the name of tolerance.

In addition, he said, the Supreme Court ruling "has shut down debate just as we were starting to hear new voices - gay people who agree that children need their mother and father, and children of same-sex couples who wish they knew both their mom and dad."

As an example, he pointed to Heather Barwick, a daughter of same-sex parents, who has said that being raised in this way is harmful for children because it deprives them of their right to both a mother and a father.

Despite these consequences, Anderson does not see the legalization of same-sex marriage as inevitably being the final word.

"The Supreme Court got marriage wrong, and got the Constitution wrong," he asserted, but every American should be working to protect their liberties and freedoms – by going out into the public square and bear witness to traditional marriage.

"We can do this in our own lives, by living out the truth about marriage in our families," Anderson concluded, saying that "we also have to be prepared to make the argument about marriage, what it is, and why it matters."