Evolution is True and Christianity, and All Religions, Are Not
Atheism is a common conclusion after studying nature. What is atheism? It’s not someone who believes there is no God. Atheism is the lack of belief in a God due to a lack of evidence. This confusion is common and even found in some dictionaries. The prefix “a” means not or without and theism refers to belief.
If you wanted to know what Christianity is would you not consult a Christian who has written on the subject? If you wanted to know what constitutes the Islamic religion, would you not consult a Muslim scholar? If you wanted to know the proper definition of atheism, would it be not be best to ask an atheist who has published on the subject, rather than straw man theist arguments against atheism? (see References below and the 14 minute video presentation above).
A lack of belief can’t be a belief any more than bald a hair color, abstinence a type of sex activity, or the off button on a TV a channel. One of the better explanations I have found for a good definition of atheism is Scott Savage’s YouTube on the subject posted above, complete with brief appearances by Hitchens and WL Craig. These 14 minutes are well worth your time and also includes a section on how “agnostic” is most often misused.
I tend to apply theism to a personal god and deism to an impersonal one that does not interact with its creation. Atheism is such a loaded term that it often carries negative connotations that are not accurate. Other terms may be helpful to use are non-theist and anti-theist. Of course, multiple descriptors can be applied to a single individual. Other atheist organizations agree with the proper definition of atheism. Much more importantly, atheism is not a religion (Worships what? No creeds. No supernatural belief and different atheists can have different world views - note Stalin vs. Sagan for example).
Secondly, atheism does not tell you about the person. It's just a tentative very secure conclusion due to a lack of evidence for a supported claim of God. It's not a philosophy of life explaining what a person believes in terms of morals, meaning and purpose in life for example. Most atheists adopt secular humanism as their world view but certainly Stalin and Pol Pot did not.
Atheism is frequently and falsely linked to immoral values due to especially some despotic communist leaders. As demonstrated here, atheism is not a worldview and does not tell us anything about the values a person holds. In fact, there are atheist disaster relief agencies and organizations that help the poor and homeless. See for example: https://seculardirectory.org/charities/