"As with [any] ideology, atheism can be part of a philosophy." It is not a philosophy.
It's the usual semantics war again.
Yes, what you state above can be taken as truthful, as can:
"As with any ideology, theism can be part of a philosophy." It is not a philosophy.
This is also true.
However, the basic acceptance of whether a God exists or not is one of, if not the basic building block of an individuals philosophy.
BA