The truth is always more difficult than a symbol or emotion.
So most people pick the easy answer, which is less complex than reality, so causes unintended consequences when tried in reality.
As a result, they create and reinforce among each other a "fake reality" made of these symbols and emotions.
Then, when their grand ideas fail, they blame someone else and refuse to change.
It's how any group, including a civilization, meets its end.
Just like our motto here -- The truth is unpleasant and therefore unpopular -- there's truth to the above: people prefer pleasant illusions to difficult realities.
This isn't to say that reality is bad, just that it's less pleasant than an oversimplification. Groups of people can tell each other lies, and then agree on those lies, and using conversation and emotional appeals (guilt, pity) enforce them on each other.
That's how any group, whether a small company or a rock band or a civilization, meets its end: from within.