An increasing number of Americans profess no religious belief, but there may be something intrinsic about atheism that makes organizing into effective groups problematic. Here is an argument that this limits their political effectiveness:
Evangelical Christians make up about one-quarter of the adult
population, but they are the core of the Republican Party, and as
Republican politicians know well, evangelicalism is strengthened by the
continual re-creation of a strong group identity threatened by outside
forces. And if the threatening others outside the group seem to be not
just a disparate collection of people who are "not like us" but a
coherent tribe themselves, able to act with purpose and malice, that
threat becomes all the more powerful a motivator. So the more visible
secularists become, the greater the opportunity to bind evangelical
voters more closely to the GOP.
But it won't be easy for secular Americans to become better organized
as a political force, even as they increase in number. The major
impediment to that kind of organization is the fact that it is very
difficult for secularists to conceive of themselves in tribal terms.
Most tribes, whether of nations or ethnicities or sports fandom, can
easily demarcate their membership—it's the people who look like us, or
talk like us, or dress like us. Tribes organized around religious belief
have rituals, sacred texts, and physical spaces that all serve to bind
the participants together. Atheism has none of these things—most of the
time it's an individual choice, made and kept alone.
