(CNN) - The Methodist Church added "united" to its name after merging with another denomination in 1968. But for much of the past 52 years, unity has proved elusive.
That's been especially true at meetings of the church's top legislative body, the General Conference, where factions have fought for decades about sexuality and Scripture. After the church strengthened its bans on partnered LGBTQ clergy and same-sex marriage last year, many Methodists argued that a split was likely inevitable.
"The situation here has become so toxic that the church was basically dysfunctional," said the Rev. Keith Boyette, leader of the conservative Wesleyan Covenant Association.
Last week, Boyette was one of 16 United Methodist leaders to propose a divorce decree for their church. With the help of a renowned mediation lawyer, conservatives, liberals and centrists gathered in secret for months, sweating the details of a pact they hope will split the church without producing messy and expensive lawsuits.
Jan Lawrence, head of the pro-LGBTQ Reconciling Ministries Network, called the deal imperfect, but said it will "end the othering and marginalization of parts of God's creation."
While presenting their proposal last week, Methodlst leaders offered themselves as an example to a polarized country. Look how we agreed to disagree and walk away, they said.
Other Methodists agree: Only lawyers like costly lawsuits. But some also wonder how dividing the church could be a good thing.
The United Methodist Church is one of the few places in American life where people as different as Hillary Clinton and Jeff Sessions can share the same pew. If the proposed schism is approved, that likely won't be true anymore.
More churches are breaking in two over LGBTQ issues
In recent decades four of the seven traditional mainline Protestant denominations have split up over homosexuality or related issues, such as the interpretation of Scripture and frustrations over rehashing the same debate for decades.
They read like an alphabet soup of American religion: The American Baptist Churches USA, the Episcopal Church, the Evangelical Lutheran Church in America and the Presbyterian Church USA.
Religious historians say we haven't seen so many church schisms since 19th-century debates over slavery, when denominations split into Northern and Southern branches.
And the current breaks over homosexuality could be just the early tremors of an earthquake that will scatter the country's entire Christian landscape, some scholars argue.
"The mainline Protestants are like the shock troops," said James Hudnut-Beumler, a professor of religious history at Vanderbilt University. "They absorb the first body blows. But as the mainline goes, so more conservative and evangelical will go eventually."
Some mainline churches are going through an identity crisis
So what is a "mainline Protestant," why are they fighting, and why do I care if they break up?
According to some historians, the term "mainline" derives from the suburbs outside Philadelphia, which, like a lot of towns in America, built churches along its major thoroughfares, aka the "mainline."
These Baptists, Episcopalians and Presbyterians dominated American life in the 20th century. They were old, established and largely centrist.
But mainline Protestant denominations have declined for decades. The pastors and church leaders considered themselves "custodians of the culture," and for many years they were. And then the culture changed.
Now some mainline denominations are going through an identity crisis, said Maria Erling, a professor of church history at United Lutheran Seminary.
"If you try to be welcoming and open to all people, the question becomes: Who are you? What are you offering?" she said.
At the same time, mainline Protestant birth rates are declining, baptisms have dropped and the pews are filled with grey hairs, if they filled at all. According to one study, less than 4 in 10 millennials raised in a mainline Protestant church stay there.
The benefits of breaking up
Conservatives have been leaving, too, founding or joining more theologically traditional denominations.
In 2009, conservative Episcopalians broke away and founded the Anglican Church in North America after decades of debate over LGBTQ clergy.
The new denomination, which does not ordain LGBTQ pastors or allow same-sex marriages, is small. It has about 134,000 members, while the Episcopal Church has 1.5 million.
But it is adding new members and congregations nearly every year, said the Rev. Andrew Gross, a spokesman for the Anglican Church in North America.
Some churches and dioceses are still battling the Episcopal Church in court over church property. But for the most part, Gross said, they have moved on.
"Honestly, we don't spend a lot of time thinking about the past or fighting old battles anymore," he said.
Liberals who remained with their home denomination seem just as relieved to have laid down their swords.
The Evangelical Lutheran Church of America fought about allowing LGBTQ clergy for decades before finally voting yes in 2010. Thousands of conservatives then defected to form a new church.
Without those conservatives in the fold, liberal Lutherans were able to make major moves in the church's last General Synod, voting to declare itself the country's first "sanctuary church body" for immigrants. It's the kind of bold step that would have been thwarted or put off to deal with sexual issues at past synods, Lutherans say.
So there is a benefit to breaking up. Both sides seem happier, more focused on their missions and less concerned with internal battles.
But any time a church as big as the United Methodist Church threatens to disintegrate before our eyes, it's worth asking what's lost.
There's value in worshiping beside someone who's different
If the Methodist proposal is approved at this summer's General Conference in Minneapolis, it would be by far the largest Protestant schism in decades.
As many of 30% of the church's US members and 80-90% of Methodists in Africa and Asia could leave the United Methodist Church for the new conservative denomination, Boyette told CNN. That would drastically reduce the church's roll of 12.5 million members, about 7 million of whom live in the United States.
Protestants, born of a split with the Catholic Church, are pretty well-practiced at spiritual break ups. There are 47,000 Christian denominations in the world, by one estimate, including dozens of Methodists branches in the United States. Protestants gonna protest, you know?
And denominations, despite their functionality, get a bum rap. Nobody likes a bureaucracy, even if helps connect and pool resources for charities around the world. And for generations, big-tent denominations like the Methodist Church helped hold the country together.
Now, online and in real life, we seem to only want to associate with like-minded people, clustering into our dissent-free echo chambers.
Churches can force us out of those bubbles, helping us connect across all kinds of social, political and racial barriers. There's value in worshiping next to someone different from you.
There's also a spiritual reason to lament Christian divisions, said Will Willimon, a bishop in the United Methodist Church and theologian at Duke Divinity School.
In the Garden of Gethsemane, just before he was crucified, Jesus prayed that his followers would live "as one." Every new denomination -- even the Protestant Reformation itself -- can be seen in some ways as a failure, a step away from that prayer, said Willimon.
"I wonder in the present moment, if Jesus Christ is looking at us and saying, 'Look at what you all are fighting over now.'"