Atheism is a relational statement to belief systems that have at their focus a god or gods.  There may be no deity involved, but even atheists are subject to the ways in which culture is influenced by those who do espouse a belief in g-d(s).  Racism, homophobia, institutionalized misogyny: all of these are largely supported by religious beliefs and their resulting practices with which atheists must contend.

There need be no g-d(s) for transtheology to be relevant; a transtheology has room for those without faith as full participants in the vast array of interconnectedness to which we all belong.