Technically, this cannot be true. Babies cannot disbelieve something they do not understand. Still, there shouldn’t even be such a word as atheist. There is no such word for not believing in fairies, or gremlins, Santa Claus (A-Santaclausist?). It is not until we acquire language that we are indoctrinated, usually by our parents, into believing what they believe, whether or not it is backed by evidence, logic and reason.
It is human nature to trust authority, beginning with our parents. That trust is then extended to our immediate family, and then out to our relationships at church, at school, and the workplace. We tend to surround ourselves with like minds, and therefore it is again human nature that we suffer from confirmation bias. That is, we tend to focus on that information that supports our beliefs and opinions, and ignore or reject the rest.
Some of us, as we expose ourselves to new concepts, new ideas, and especially to science, will begin to question some of the beliefs, especially the faith-based beliefs, that were embedded in our early indoctrination years. This can result in a social crisis that can affect all our relationships, and in severe cases, even our mental health.
The word atheist is a pejorative amongst the majority of Americans; a label for someone who has no morals, a hedonist, a bad person–or even politically, a socialist, a communist or anarchist.
Surveys have shown that atheists rate lower on the hate scale than rapists. And Americans say they would rather have a Muslim president than an atheist to occupy the highest office in the land. I suspect there are a number of past presidents that are, in their hearts, atheist. But they must play the game and act the part if they want to get elected.
Like me, many atheists remain in the closet for fear of persecution and rejection, similar to what homosexuals have had to endure for centuries. Threats of death and injury is why the most strident, outspoken atheists must hire security for themselves and their families.
Today, even gays receive a certain amount of acceptance amongst the more liberal religious organizations–well, as long as they profess a belief in the Christian or Jewish god. Increasingly, openly gay candidates have successfully won positions in government. Perhaps one day atheists will be so fortunate.