I can’t put it any better than Sam Harris:
This is directed at theists who might stumble across this post.
One of the most common accusations leveled against atheists are that they’re angry, so angry. For many of us that’s true, we are angry. Yet in order to understand why we’re so angry, let me ask you something.
Lets pretend for a moment, a little thought experiment if you will. I promise it won’t hurt or do anything to your faith, it’s just an experiment.
Imagine that you died, it doesn’t matter how, only that you’re now dead, and the afterlife is not what you were promised. Instead of heaven or closeness to some deity, you are made aware of the fact that their is no god, there never was. You look down at the earth, all the people on it, all the things we do to ourselves and each other in the name of a god; a god you have just learned never existed.
How would you feel? How would you react to the magnitude of the consequences and implications?
Sure you would see some good things being done in the name of this mythical god, but what about all the suffering? Suffering that is needlessly prolonged by those claiming to act in the name of a god you just learned never existed.
How would you react to this revelation’s implications? Think of all the time spent in pointless prayer instead of action, all the money spent building monuments and structures to a nonexistent being. All the money that lines the pockets of those who claim to speak for this being. What about all the wars, genocides, book burnings, shootings, suicide bombings, the death in perpertrayed in the name of this non-existent being? What about all the people who are forced to marry those they don’t love because of religious prescriptions? What about the millions of people who have their genitals cut in keeping with religious commandments? What about the honor killings? What about all the people who were forced to live in a miserable marriage, perhaps where they were even beaten, because their faith frowned on divorces?
How would you feel?
What about your life? What if you spent a large amount of time, effort, and money investing in something you later found out to be a scam? What dreams could you have accomplished if those energies were directed elsewhere? What about those things you denied yourself that you could have enjoyed? What about foods or drinks you refused to try for ultimately pointless religious reasons? What opportunities to live did you turn down in preparation for death, only to find now that you’re dead, those preparations futile, those opportunities gone forever?
Hypothetically, as all these realizations hit you like a tsunami, how would you feel as you slowly fade to nothingness?
I’m willing to bet you would feel an intense anger, possibly betrayal.
Hold that feeling in your mind for a moment. Now imagine that you weren’t fading to nothingness, that you weren’t dead. Imagine you were still alive, yet with this knowledge, and now you had the chance to do something about it. How would you feel? What would you do?
If you answered that you’d be angry and outspoken in your efforts to make the world a better place and end suffering, then you now understand where a lot of “angry” atheists are coming from.