This article is from the Atheism FAQ, by mathew meta@pobox.com with numerous contributions by others.
It is an unfortunate human tendency to label everyone as either "for"
or "against", "friend" or "enemy". The truth is not so clear-cut.
Atheism is the position that runs logically counter to theism; in that
sense, it can be said to be "anti-religion". However, when religious
believers speak of atheists being "anti-religious" they usually mean
that the atheists have some sort of antipathy or hatred towards
theists.
This categorization of atheists as hostile towards religion is quite
unfair. Atheist attitudes towards theists in fact cover a broad
spectrum.
Most atheists take a "live and let live" attitude. Unless questioned,
they will not usually mention their atheism, except perhaps to close
friends. Of course, this may be in part because atheism is not
"socially acceptable" in many countries.
A few atheists are quite anti-religious, and may even try to "convert"
others when possible. Historically, such anti-religious atheists have
made little impact on society outside the Eastern Bloc countries.
(To digress slightly: the Soviet Union was originally dedicated to
separation of church and state, just like the USA. Soviet citizens
were legally free to worship as they wished. The institution of "state
atheism" came about when Stalin took control of the Soviet Union and
tried to destroy the churches in order to gain complete power over the
population.)
Some atheists are quite vocal about their beliefs, but only where they
see religion encroaching on matters which are not its business -- for
example, the government of the USA. Such individuals are usually
concerned that church and state should remain separate.
 
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