I assume that every atheist already has a nicely planned out reason to fight religious dogma and enforce the separation of Church and state, but I will feature a common reason here:
Christian: “Why do you try to fight the belief in God? You don’t try and fight the belief in Santa, or Zeus?”
Well, let me tell you something. Santa is not used as the main reason for many people’s decisions in life.
Santa is not used as a justification or excuse for war, hatred, bigotry and discrimination.
People do not waste millions of dollars building useless buildings dedicated to Santa.
Gays are not denied rights because of Santa.
The words ‘in Santa we trust’ are not on US money, and likewise, Santa is not in the pledge.
And people do not try to fight science using Santa.
Things like Santa, the Tooth Fairy, Zeus, etc. are not used to do these things, but God is. Christianity is a religion that tries to enforce complete control over people’s lives, it is used as a justification for war and hatred, and it is even invading the US government. And that is why I fight religious dogma.