I find it a bit difficult to understand whether you defend religion on the whole or just your particular version of Christianity? If you ask me a question "Do you know for sure that there is no invisible powerful beings affecting our lives”, - of course I would have to say: "No, I don't know". But real religions are precise. They have sacred books which content could be proven historically incorrect, they’ve got creation myths which could be shown to be just myths and shouldn’t be told at schools instead of science, they got moral code which could be shown unkind. Religions can have rituals which my moral duty could be to declare cruel and ideas which I feel I must warn people as of potentially dangerous. For me Atheism is not about abstract unknowable things, it’s about concrete details.
People are very different in respect of what they cherish the most - hence their understanding of their own religion vary. For you, the emotions are the most important things, for others they will be something else: dogmas, rituals, moral, sacred texts, model of the world, power, hierarchy and so on. Please don’t make all believers to be just like you.
Atheists are not a political party or a club, it’s just all sort of independent people who don’t subscribe to any religion while you subscribe to just one of them - this is why there can't be much emotions involved in the idea of Atheism. “I probably hurt your “atheist” feelings,” – sarcastically said one Christian to me. I don’t have any “atheist” feelings. I am human and I have human feelings. I can’t understand why having ordinary human feelings (which of course could be hurt) counts by believers as something less important than them having their “religious” feelings… By the way that praised by you highly emotional state that many religious people experience, together with non-questioning, dogmatic thinking, may be responsible for horrific things believers sometime commit. We all got natural empathy of social beings - towards other human beings and some animals, but there are situations when it could be overridden. On the mass scale - by feelings and ideas provided by religion, nationalism or ideology.
You are saying that a lot of Christians were atheists at some point. A lot of atheists were Christians (me included) so we know what we are talking about.
I noticed that believers like to say "we are so similar to atheists" or “atheists are really believers too” - like they feel some sort of insecurity, the fear of being left behind.
I love the comparison with Stamp Collectors and use it all the time myself. If all believers were like Philatelists I don’t think you would had much opposition at all! Just minding your own business... Philatelists (and atheists too!) never knocked on my door, approached me on the street, came to my kids' school to teach their ways without my consent… Stamp Collectors (as far as I know) never claimed that all non-Philatelists are perverted sinners, lost souls and will burn in hell forever, they never invented a law punishing non-Philatelists for not bothering about stamps… They never executed anybody who said that stamps are rubbish. If you reject barbaric things like that it doesn’t mean that all believers do!
It is not the pleasure to oppose religion and humiliate religious people which moves atheists like me but the desire to warn of the dangers of religion, especially of the dogmatic set of mind - listed above and others, sometime much less obvious.
Honestly, which side, religious or non-religious, exhibits throughout the World and exhibited through the History more aggression and intolerance?