I mean the trouble is most religions have been used to spread peace and war. The problem is not religion, it's just the tool. The ruling class will pick up another tool of propoganda to convince the oppressed to act outside their best interests. Feeling smug about being unreligous leaves you vulnerable to alternative methods.
Racism, sexism, nationalism, homophobia, and ageism all serve to divide us whether on a religious or "scientific" basis. No matter the justification we must examine what the end goal of all methods of social control is.