That was the phrase used to explain why the Tzarnaev brothers set off bombs. Pretty much the same thing is happening in the LDS church, though the bombs are metaphorical.
We can find places in cyberspace where we are surrounded by people we agree with and it fuels itself. (That's why I like RfM! Har Har)
If we only surround ourselves with people who agree with us, we don't notice when we start to cross the line.
Look at N. Korea. I'm guessing most of the people who are so into their "beloved leader" have no idea how bizarre they have become. (Insert your own example here.)
It gives me pause to seek diversity in what I read and what I do.