As last weekend's Reason Rally on the National Mall showed, the secular movement in America is reaching a critical mass. When 20,000 enthusiasts show up on a rainy day to celebrate secularity, joining together to oppose the unquestioned exaltation of religion in American public life, there can be little doubt that change is coming. As president of the American Humanist Association, one of the rally's major sponsors, this left me exhilarated, that the destructive anti-intellectualism of the religious right might finally be meeting its match. Those rallying for reason were a diverse group, across all lines of race, age, and class, and they hopefully represent a movement that will escort the religious right off center stage, into the history books.

As I looked out at all the young people cheering for Richard Dawkins and Tim Minchin, however, I also realized how important it is that humanism, and not just atheism, be part of this revolution. Indeed, for humanists, the success of the secular movement is only half the battle. After all, humanism is not just an arm of secularism, but a hybrid of the secular movement and the progressive movement.

If this seems difficult to understand, bear in mind that Karl Rove is reportedly an atheist, but he certainly would not find the American Humanist Association to be a comfortable fit for his worldview. Atheism, which addresses only the issue of the existence of gods, has no social, political, or economic , nor must an atheist reject all supernaturalism. An atheist might believe in astrology, , magic, and of course, even worse, the conservative of Karl Rove (though thankfully most don't).

The rights of atheists and other nonbelievers (including humanists) are definitely worthy of a rally, for in America, the unfair stigmatization of secularity has had terrible consequences. Not only has it empowered the religious right, but it has made an important demographic—secular Americans—unelectable. Creationists who believe the world is only a few thousand years old routinely win elections, but open atheists in public office are almost nonexistent. And we wonder why the country is such a mess?

Yet, even as I relished every moment of solidarity with fellow secularists on the National Mall, I was mindful that the secular movement is only half the battle. Respect for nontheists is an important step, but the core values of humanism—critical thinking, human rights, naturalism, women's rights and reproductive rights, church-state separation, social and economic justice, peace and global , environmentalism, restraint of corporate power, etc.—cannot be forgotten in this secular revolution. The alternative—an America where atheists can get elected, but those atheists are of the neocon model or worse—is not an acceptable end result.

In recent years, past generations of humanists, even going back to John Dewey, have sometimes been criticized for downplaying secularity, for avoiding the term "atheist" out of of vilification. By focusing almost exclusively on progressive social and political issues while being coy about their secularity, past humanist activists arguably empowered religious conservatives. (Dewey and others, for example, even used God-language and other strong religious terminology, despite their disbelief.) Unwittingly, this contributed to the marginalization of the secular demographic by creating a sense of false unanimity on the importance of theism and . As experience has shown, this approach has proved disastrous for secularism and progressivism, as both have gotten crushed in the modern era by the religious right and its conservative allies.

Surprisingly, standing on the National Mall in the midst of the energized, forward-looking secular movement of 2012, I felt a slight pang of nostalgia, a longing for that progressive strand of humanism. As I enjoyed the secular karma with the college kid next to me in the Hitchens T-shirt, it occurred to me that without both oars in the water—secular and progressive—this boat can't take us where we want to go. These newbies are ready to battle the religious right, but have they considered what their more secular society will look like?

Ironically, most of these students are indeed humanists, not just atheists and agnostics. They are tolerant and peaceful, and they see racism, , militarism, homophobia, and tribalism as phenomena that belong to the past, not the future. They don't want unrestrained corporate power, nor do they want government dictating what happens in the bedroom. They are proudly secular, seeing the emergence of their lot as a step toward a more enlightened society. In the longer term, however, they must realize that the secular movement is but one campaign in a larger war.

Indeed, if today's well-meaning youth aren't careful, a successful secular movement could nevertheless result in a country that is still hostile to most humanist values. In a more secular America, powerful corporate interests would no doubt still push hard for their anti-humanist agenda, most likely advocating for a culture that reflects an Ayn Rand style of secularism that, like many of today's most strident conservatives, sees the poor as parasites who deserve nothing, that sees social justice and equality as despicable concepts. No humanist wants that.

This is why humanism, not just atheism, must be an important part of the emerging secular movement. If yesterday's humanists erred by ignoring secularism to emphasize progressivism, today's had better also learn the importance of keeping both oars in the water.

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Video produced by The Thinking Atheist