ELIGION HAS coursed through this young century like a rip-tidethroughanotherwisecalmwaterway.Adecadeor two ago, when atheism was the popular default setting, it would have seemed unbelievable that thestrongestculturalcurrentofthethirdmillenniumwouldbemonotheism.Yet everywhere we look today, in almost every aspect of publiclife,religionisstagingacomeback.

In Turkey, the defiantly secular state established by Mustafa Kemal Ataturk in 1920 is facing pressure from Islamist parties. In America, Creationists want their theory of how life developed to feature alongside Darwinism in science class. In France, there is anongoingrowoverthe wearing of the veil. In the UK, there are worries about the roleofevangelicalreligionincity academies and anawarenessthatreligiousinterestgroupsfeelemboldenedandempowered.Andsowehavehad Christians trying to force an opera off the schedulesofournationalbroadcaster, Sikhs storming a Birmingham theatreand,justthismonth,aturbulentScottish cardinal proposing a ban on communion for Catholic politicians who back abortion.

Whyallthisnow?TheeventsofSeptember11,2001,theriseoftheneoconsinAmericaandthe so-called war on terror are the short-term reasons. But there are many who look further back and see the seeds of this religious renewal in thevictoryofthemujahidinin Afghanistan, in the fatwa against Salman Rushdie, in the fall of the USSR.

As religion rises to its feet, however, so too does its shadow - atheism. From across Europe and America has come a slew of humanists and philosophers eager to reassert their position and argue against a faith-based system of ethics. In place of pulpits and soap-boxes they have publishers and chat shows and they have been dubbed The New Atheists.

TheNewAtheistsareledinthiscountrybythe philosopher Anthony Grayling, author of Against All Gods (published in March), and the scientist and arch-Darwinist Richard Dawkins, who last year published The God Delusion, a New York Times bestseller and his most controversial book to date.

In America there is Daniel C Dennett, who wrote BreakingTheSpell:ReligionAsANatural Phenomenon, and Sam Harris, whohaswrittennotonebuttwobestsellersonthesubject, The End Of Faith and Letter To A Christian Nation. Both Harris and Dennett are American and, unsurprisingly, it's in the Land Of The Freethatdebatehasragedmostfiercely.Dennett,oddly,referstoatheistsas "brights".

Thenthereisthearchpolemicist Christopher Hitchens. His tome God Is Not Great: The Case Against Religion hits the bookshops here next week.

Finally,inFrance,thehomeofsecular republicanism, the philosopher Michel Onfray has joined the battle.

Onfray's In Defence Of Atheism: The Case Against Christianity,JudaismAndIslam has already sold more than 300,000 copies in Franceandhasjustbeenpublishedin English.

ItisAnthonyGrayling,Christopher Hitchens and Michel Onfray I have setouttotalkto,inaseriesof encounters aimed at teasing out what they believe - and perhaps resolving a few questions of my own.

WhatIhearmostclearlyisthis:thebattlelineshavebeendrawn.

So which side are you on?