The Presbyterian Church (USA), or PCUSA, is the fourth major denomination of mainline Protestantism to support marriage equality, following in the steps of the United Church of Christ, The Episcopal Church, and the Evangelical Lutheran Church in America.

While these developments make news, generally unreported is that these churches came to their positions after years of careful deliberations, discussion and debate.  Unlike most of the opponents of marriage equality, these churches have democratic governance structures.

Also largely unreported is how outside Christian Right agencies have exploited the democratic polities of the mainline churches, in an effort to degrade their capacities to advance social justice.

The reasons for all this have everything to do with the successes of what the churches call their "social witness" across the 20th Century.

From the enactment of child labor laws, to advancing the African-American civil rights movement, to ending the war in Vietnam, to elevating the role of women and of LGBTQ people, the major denominations of mainline Protestantism have provided moral authority, leadership, and resources that were vital to these movements for social change.

And yet, if you read most of the media you might be led to believe that the only reasons people leave these churches is because of their positions on such things as ordination of women and gay people; reproductive justice, and/or and marriage equality.

The decline in membership in these churches is painfully real. But there is much more to the story of why people leave the churches and people they love.

One of the primary reasons for the departures is a sustained pressure campaign by external interests, seeking to pit mainline Christians against one another; manipulate democratic processes to be unnecessarily divisive; and ultimately diminish and displace these historic denominations which have held a place at the center of American culture for centuries.

One of the main agents in this war of attrition has been the Washington, DC-based Institute on Religion and Democracy (IRD), funded by the same group of conservative foundations that brought the likes of the Heritage Foundation to Washington, DC. IRD has been primarily funded by neoconservative and Christian Right interests that view the mainline churches as obstacles to their regressive, and sometimes overtly theocratic, political agendas.

For many years, IRD served as the hub of a national network of conservative denominational factions called the Association for Church Renewal.

These organizations, which call themselves "renewal" groups, variously seek to neutralize church tendencies of which they don't approve; drive out staff they don't like; and seek to take over the churches, but failing that - take  as many churches and assets out of the denominations as possible.

Media of all sorts have tended to treat group spokespersons as credible voices of dissent, while turning a blind eye to the malevolent intentions of many of these groups and individuals. For example, James Tonkowich a minister in a schismatic denomination that split with PCUSA in 1970, served as the president of IRD from 2006-2009.

He characterized the mainline churches as marked by "division, polarization, and discord."

By 2012, he had not only became a Catholic, but claimed that the best way for Protestant churches to solve their problems was to, like Tonkowich, also become Catholic.

In short, the Christian Right's narrative that mainline church membership is declining primarily because of differences over things like marriage equality unravels when subjected to scrutiny.

In the largest study of its kind ever conducted, scholars at the Hartford Institute for Religion Research at Hartford Seminary debunked the narrative in 2007.  

Noting media reports claiming people were leaving churches over issues related to homosexuality, the study found that the main reason people left churches was not due to theology or ideology, but because of unhappiness in the wake of bitter in-house conflict.

"Congregations that have experienced major conflict," the study concluded, "are quite likely to have declined in attendance."

But, the study continued, "congregations with no conflict during the previous two years are least likely to decline and most likely to grow."

The antidemocratic elements that lead and underwrite IRD have been pleased to exploit the internal debates and manipulate the mechanisms of democratic governance in the mainline churches to achieve their larger ends. Their efforts have worked to some degree. But not nearly as well as they had hoped.