Assuming anything in that article is true about "The Family", let alone broader Christianity, even accepting that article's arguments as true, it makes clear that "The Family" is not representative of broader Christianity, only the secret plans of "The Family". I don't see having a private meeting between the U.S. and Russian presidents to negotiate peace without a huge public spectacle as necessarily bad. Any more than having Dennis Rodman meet with Kim Jong Un was bad. Or Jesse Jackson secretly negotiating the release of hostages. Or Ronald Reagan meeting with Pope John II to bring about the collapse of communism in Poland.
As an occasional churchgoer and occasional participant in Christian events, I've certainly seen that Christianity in the U.S. has become less WASPY and exclusive to the white middle/upper class, and much more international and multicultural, whereas in the 1970's Christianity was more in pockets of white churches, black churches, Hispanic churches, separate from Jews, and often anti-Semitic. Whereas now (you could google it) Evangelical Christians actually give more money and support to Israel than the American Jewish community.
I'm definitely not a typical Christian, but I do think I'm representative in this way, that despite not being Jewish, as a Christian I believe supporting Israel against persecution is essential for Christians, because Jews are God's chosen people and the instrument through which God gave us the Old Testament and New Testament, and through which God continues to fulfill prophecy of the End Times. Essentially Christians are a sect of Judaism. Up until Jesus, the Bible and salvation were exclusively offered to the Jews. With the life and teachings of Jesus, it became a message and salvation offered to the entire world. And far from judgemental or elitist or racist (as "The Family" is accused of being) it is a salvation and unity offered to all. Including criminals and the enemies of Christianity. In the New Testament, Paul was imprisoned by the Romans, and realized that he was sent there to spread the gospel to the damned and lost there. Christ during his crucifixion had two other criminals on crosses right next to him, one of whom professed his faith in Christ and was saved. And again, as I cited above, God far from hating or wanting to condemn anyone, most celebrates the return and redemption of the prodigal son. Criminals, drug addicts, even enemies and murderers of Christians, as Paul was in the book of ACTS (a traditional Jewish elder who killed Christian sectarians, before his conversion), or homosexuals, are all offered salvation and welcomed back into the brotherhood of Christianity.
So it's really absurd to allege Christianity, or the sect of "The Family", is some elitist authoritarian Hitler-like group to force or trick an entire nation into Christianity as some political force. That goes against the free-will individual choice that is the core nature of Christian faith.
Christianity didn't seize authoritarian control of the country when Reagan was president. (Although it sure was portrayed that way in the liberal media!) Christianity didn't seize authoritarian control under George W. Bush. (Who actually was a devout born-again Christian who prayed in White House meetings. But even so, I saw interviews with Christian leaders who felt used and marginalized by the Bush White House despite their strong aid in getting him elected.) Christianity under Trump has seen restored some of their religious and political free speech rights, but is hardly seizing authoritarian control under Trump either. Trump is supportive of Christianity, and keeping his word to Christians better than Bush. But while likely being a Christian on some level, Trump is not the same kind of born-again devout guy that George W. was. Obviously Trump's lifestyle, his multiple marriages, and extramarital/adulterous affairs with women, he isn't one to make too much a show of devoutness.
If you want to whip up a scary spectre of a Christian threat, M E M, you could always point to the Westboro Baptist Church. Which has maybe 30 members last time I looked, is disowned as hateful and not Christian in spirit by any other known Christian denomination.
Or maybe the Christian Identity movement, that is basically the last remnant of the white supremacist gleichschaltung re-invention of Christianity under Nazi Germany, to make Christian religion conform with the ideology of Nazi Germany. And all the thousands of true Christians who refused to practice it were thrown in Nazi concentration camps. A Christian Identity movement that has maybe a few hundred members in the U.S., probably all of whom are on an FBI watch list.
