The mainline churches are all in severe decline. Some of this related to the fact that (((millennials))) don't reproduce enough, but just as much comes from their getting too liberal too quickly (e.g. endorsing gay marriage, having Tumblr-tier political stances, making anti-anime sermons, etc.). It seems unfortunate that people are abandoning some of the more historic Protestant churches and joining (((evangelical))) congregations.
Presbyterians exclaim "We are not dying. We are reforming!" after losing 90,000 people.
https://web.archive.org/save/https://juicyecumenism.com/2017/05/24/pcusa/
http://juicyecumenism.com/2017/05/24/pcusa/
Episcopalians are hemorrhaging members and suing congregations:
https://archive.fo/U4WRB
http://www.beliefnet.com/faiths/home-page-news-and-views/why-is-the-episcopal-church-near-collapse.aspx
United Methodists Church is in decline and you're racist for noticing REEEE.
https://archive.fo/ajqC7
http://www.umglobal.org/2017/03/american-umc-decline-is-white-people.html
Lutherans: Also doomed.
https://web.archive.org/save/https://juicyecumenism.com/2013/08/14/always-declining-the-evangelical-lutheran-church-in-americas-stillborn-quarter-century-of-existence/
http://juicyecumenism.com/2013/08/14/always-declining-the-evangelical-lutheran-church-in-americas-stillborn-quarter-century-of-existence/
WaPo claims that mainline Protestantism only has twenty-three years left.
https://archive.fo/4AXl5
https://www.washingtonpost.com/news/acts-of-faith/wp/2017/04/28/if-it-doesnt-stem-its-decline-mainline-protestantism-has-just-23-easters-left/
What do, /christian/? Should we wait for one of these churches to get small enough and then try to colonize it? We could take over the Episcopalian Church and make piracy a sacrament.