Over the past 150 years, there have been many groups who have sought the North American dream of "liberty and justice for all." Examples are:
Americans African seeking an end to slavery.
Women campaigning to get universal suffrage.
And now, gays and lesbians are seeking the same equal rights and protections enjoyed by other groups, including the right to marry.
This final conflict over homosexuality is a little different from the two conflicts based on race and gender. Being an African-American or a woman was never considered a crime. But being a sexually active person with a homosexual orientation was, theoretically, a crime in 13 states until the middle of 2003. Being Black or female was never considered an unacceptable -- i.e. immoral -- state. But same-sex sexual behavior was considered "not acceptable" by most American adults until about 1998. It is obvious whether a person is Black or female. It is not obvious whether a person has a homosexual orientation. A gay or lesbian could stay in "the closet" and avoid discrimination. African-Americans and women could generally avoid hatred by restricting their behavior; gays and lesbians are often hated and oppressed because of their sexual orientation.
The "warfare" among science & religions:
Normally, there are minimal conflicts between scientists and theologians. They usually work in different areas of interest. Theologians are rarely interested in the tensile strength of steel. Scientists -- at work, at least -- are rarely interested in the soul, salvation, Heaven or Hell. But there are shared areas where both scientists and theologians promote their own beliefs. Often, these beliefs are in conflict.
As of 2003, the main areas of religious conflict are the origins of the universe, discipline of children through corporal punishment, and various human sexuality topics. Homosexuality is measurable and thus is a legitimate area for human sexuality