From Wood, a Christian, at The John Heron Project. These are his main points, read the whole thing! (my comments are in italics,)
It’s not what they believe that’s so similar; it’s the way they believe it. And there’s a lot of similarities in their approach.
1. There is no salvation apart from us (only we have the true understanding)
2. The world is worthless (until we take over)
3. Compromise is a really bad thing
4. Don’t listen to them, they’re dirty splitters (Especially the Judean People’s Front)
5. The whole world works like we say it does (even the parts that don’t)
6. We’re working towards our own version of the apocalypse.
Number 6 is the most dire, as their respective apocalypses generally mean that multitudes of non-believers (be they non-Christian or bourgeoisie) will die so that the new perfect world can then be born. To which some might respond by quoting The Doors, “cancel my subscription to the resurrection.”
Sure, many ECs and RMs are not True Believers, the mindset detailed in the classic on the subject by Eric Hoffer. But Hoffer doesn’t delineate between mass social movements, seeing all of them as potentially dangerous, saying if you join one it’s because you feel inadequate and not because of genuine perceived injustices. For him, it’s about the personal, and not about social issues.
Bury The Chains details how “12 angry men meeting in a printer’s shop in London in 1787” gave birth to a mass movement that eventually ended slavery in Britain. They invented the economic boycott, petitioning of elected officials, and lapel pin as organizing tools, essentially giving birth to what we now call social organizing. From those twelve True Believer acorns, a mighty oak grew, even if at the beginning the public thought the acorns were nuts. This was a social movement that needed to happen, and it was started by angry “extremists.”
When conservatives rant that commies and socialists were active in labor unions in the 30’s, the Civil Rights movement, Vietnam War protests, and now the Iraq War protests, they are absolutely correct. Socialists organize for social change, this should come as no surprise. Lots of others were organizing in those movements too, such as people of faith. It’s always the committed, those who believe strongly about something, who start social movements. How could it be otherwise?
But the True Believer aspect can be troubling. Ask an orthodox Marxist about the purges of Stalin or Mao and you might get an uncomfortable silence, evasion, “the capitalists are lying about what happened,” or “it was regrettable but needed to be done to further the revolution.” You’ll get a similar reaction when asking a neo-Nazi about the Holocaust. It’s not something they want to deal with. At least they’re conflicted about it, unlike some evangelicals who believe they will float up to Heaven during the Rapture while unbelievers die gruesome deaths then roast in Hell for eternity. Gosh, what a merciful God they have…
When does righteous commitment to a cause cross the line and morph into fanaticism? Because without righteous commitment, not much would change.
Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has.
— Margaret Mead
Christianity may be the perfect example of the answer to your question: clearly (at least to me) the founder, Jesus of Nazareth, had a strong personal commitment based on an experience of the Ultimate. His commitment was so strong, he was willing to die for it. The nature of that commitment is still open to debate: John Howard Yoder, in his 1972 book “The Politics of Jesus,” argues that Jesus was very much a political activist.
Christianity begins with a man so committed he died for his beliefs. It evolves into a variety of forms, including both cults on the one hand and motivated individuals and small groups on the other, with mainstream religion in the middle somewhere. How does this happen?
One aspect is that to expand beyiond the initial group (in this case Jesus and his first followers) there must be structure. Structure by nature includes levels of power. Jesus’s teaching was (in my view and Yoder’s) about NOT having power. Thus the structure and the message are in conflict from the start. Throw in a Roman emperor, a multitude of kings, some power hungry cardinals, and some “reformers” who object to power being held by a few, countered by those who rejected this struggle and (in various ways) went off into the desert to seek God for themselves, and see what happens.
From what I’ve seen, a power-hungry person corrupts a message to serve their own ends. From Sri Lankan nationalistic Buddhism, to some of the evangelical splinter churches, to Marxist groups, to the Pacific Group, power twists the message, making the group more important than the result.
As to why sometimes this DOESN’T happen, I have no idea. Except that perhaps the imperfection of humankind does not reign supreme in God’s world.