When I mention I'm writing a memoir about leaving the culture wars behind, people's first question is, "Aren't you young to be writing a memoir?" This is a delicate way of saying, What can you possibly have to say? And what if you change your mind once you actually know what you're talking about? Sometimes I think they're right. But most of the time, I think that I have no choice but to write this—for myself, for my peers, and for anyone interested in understanding us.

Yes, this book is for me. Writing is not just how I communicate my thoughts but how I actually think. It's the way an experience or a fleeting thought becomes real to me instead of floating away. It's the way I catch my thoughts and turn them over and over, testing their weight and deciding whether to keep them or throw them away. For me, to write is to become, and I can't become that older, wiser person without skewering these youthful thoughts to paper, without holding them up for my scrutiny and yours. The first drafts of this book illuminated my own failure to love. Working to correct those first bad drafts has made me strive for more charity in my everyday life. It has shown me that I don't always live out the things I know to be true because complaining about falsehood is so much more convenient than living out a radical alternative.

I am also writing this book for other ex-culture warriors who, like me, grew up with signs in their fists and are trying to figure out what to do with their now-empty hands. Like me, they were raised to be activists, and like me, they probably have felt lost as their belief in the nobility of the culture wars fades away. They are looking for some worthy cause where they can channel the passion for justice and truth, bestowed by their parents, into something that actually builds people's lives instead of tearing apart relationships and destroying faith.

Some of these young Christians know what they believe. Some don't. Some have fully embraced left-wing politics; some have just decided they are no longer Republicans. Some are trying to change their chosen political party from the inside, while others remain skeptical of the entire spectrum. But all of them recognize that something is deeply wrong with the evangelical politics in which our childhoods were immersed. Today, half of young churchgoers say Christians are "too involved in politics." Almost half of young born-again Christians think the "political efforts of conservative Christians" are a problem facing America. Less than half of young evangelicals identify as conservatives, compared to nearly two-thirds of their parents. Fewer and fewer identify with the Republican Party. Where do we fit?

I hope this book reassures these young Christians that they are not alone as they navigate these difficult waters where the currents of faith and culture collide. I hope it helps them to remember that what our parents taught us about the importance of standing for truth remains valid. Perhaps their understanding of truth was wrong or incomplete. Perhaps their frenzied application of it was fruitless. But we cannot fault their passionate pursuit.

I'm also writing this for people who want to make sense of this strange new breed of Christian. Politicians are fumbling to connect with this growing segment of the population, trying to find what moves them to act. You can see it in Barack Obama's pointed outreach to the young evangelical vote—in the biblically redolent title he picked for his youth outreach, pitched so perfectly to the evangelical soul that a conservative Christian group immediately accused him of stealing it from them. Activist authors like Jim Wallis and Shane Claiborne are trying to recruit young Christians to their causes. Organizers are trying to mobilize them. Journalists are trying to understand them. You can see it in the spate of fawning articles that trot around phrases like "young evangelical" and "broadening evangelical agenda" and "increasing passion for poverty and social justice." So often in these articles and focus groups and books, the ex-culture warriors are presented as experimental subjects or generalized as a group.

But rarely are they given a voice, beyond the punchy sound bite, that explains how they got to where they are today. Our parents are the ones most earnestly trying to make sense of it all. My own mother is sympathetic but does not understand. She said she never expected to have a child who became Catholic, as my sister has done, nor one who voted Democrat, as I have done. She thinks if that's the worst we ever do, then she has little reason to complain. But still, why the change? I hope this book will help her and others to understand that this change is not a rejection of the core truths they've passed on to us but a different application of them. Our actions and beliefs are an expansion of the principles of justice and love that they imparted, not a rejection of those principles.

This book is not a liberal credo or a political platform; in fact, this book is borne of a struggle to find a faith that transcends credos and platforms. It is a halting, flawed attempt to hew a faith that is more solid and graspable than the slogans I once traced in sand.