The time for polite debate appears to be over. Atheist writers are making an all-out assault on religious faith and reaching the top of best-seller lists, in a possible sign of resentment among nonbelievers over the influence of religion in the world.

Christopher Hitchens' book God Is Not Great: How Religion Poisons Everything has sold briskly since it was published last month, and his debates with clergy are drawing crowds at every stop.

Sam Harris was a little-known graduate student until he wrote the phenomenally successful The End of Faith and its follow-up, Letter to a Christian Nation. Richard Dawkins' The God Delusion and Daniel Dennett's Breaking the Spell: Religion as a Natural Phenomenon struck similar themes - and sold.

"There is something like a change in the zeitgeist," Hitchens said, noting that sales of his latest book far outnumber those for his earlier work that challenged faith. "There are a lot of people, in this country in particular, who are fed up with endless lectures by bogus clerics and endless bullying."

Richard J. Mouw, president of Fuller Theological Seminary, a prominent evangelical school in Pasadena, Calif., said the books' success reflect a new vehemence in the atheist critique.

"I don't believe in conspiracy theories," Mouw said, "but it's almost like they all had a meeting and said, 'Let's counterattack.' "

The writers do see themselves in a battle for reason in a world crippled by superstition. In their view, Muslim extremists, Jewish settlers and Christian-right activists are from the same mold, using fairy tales posing as divine scripture to justify their desire for power. Bad behavior in the name of religion is behind some of the most dangerous global conflicts and the terrorist attacks in the United States, England and Spain, the atheists say.

As Hitchens puts it: "Religion kills."

The Rev. Douglas J. Wilson, senior fellow in theology at New St. Andrews College, a Christian school in Moscow, Idaho, sees the books as a sign of secular panic. Nonbelievers are realizing that, contrary to what they were taught, faith is not dead, he says.

Signs of believers' political and cultural might abound. Religious challenges to teaching evolution are still having an impact 80 years after the Scopes "monkey" trial. The dramatic growth in homeschooling and private Christian schools is raising questions about the future of public education. Religious leaders have succeeded in putting some limits on stem-cell research.

And the recent U.S. Supreme Court decision upholding a national ban on a procedure critics call "partial-birth abortion" - the first federal curbs on an abortion procedure in a generation - came after decades of religious lobbying for conservative justices.

"It sort of dawned on the secular establishment that they might lose here," said Wilson, who is debating Hitchens on christianitytoday.com and has written the book Letter From a Christian Citizen in response to Harris. "All of this is happening precisely because there's a significant force that they have to deal with."

Believers far outnumber nonbelievers in America. In an 2005 AP-Ipsos poll on religion, only 2 percent of U.S. respondents said they did not believe in God. Other surveys concluded that 14 percent of Americans consider themselves secular, a term that can include believers who say they have no religion.

Some say liberal outrage over the policies of President Bush is partly fueling sales, though Hitchens famously supported the invasion of Iraq.

Given the popularity of the anti-religion books, publishers are expected to roll out more. Lynn Garrett, senior religion editor for Publishers Weekly, says religion has been one of the fastest-growing categories in publishing in the last 15 years, and the rise of books by atheists is "the flip-side of that."

"It was just the time," she said, "for the atheists to take the gloves off."