Last Sunday we drove up to Rick Warren's Saddleback Church in Orange County, a collection of affluent, politically conservative suburbs south of LA. The model of a modern megachurch, Saddleback boasts over 112,000 "unchurched occasional attenders" as well as 22,800 active members – many initiated in the temperature-controlled baptismal pools on its 120-acre campus.

Megachurches are market-driven. They study demographic data and plan marketing schemes tailored to their local target audiences. The oft-cited example of a target profile, developed by Warren, is Saddleback Sam: "A well-educated young urban professional … [he] is interested in health and fitness … but is overextended in time and money, and is stressed out. He carries a lot of debt, especially due to the price of his home. He is married to Samantha, and they have two kids, Steve and Sally."

Judging from Saddleback's promotional literature, Sam and Samantha have an insatiable appetite for therapy and self-improvement. Saddleback offers a generic "Celebrate Recovery" programme and customised support groups for "ADD Adults," "Diabetics in God", "Families with Incarcerated Loved Ones" and victims of other ills.

We entered the Worship Centre, an immense auditorium shell, where Warren was preaching from a stage at the front, where an altar might have been. Saddleback assiduously avoided traditionally churchy architecture, costume and decor. Its campus was relentlessly quotidian, designed to suggest the shopping malls and office parks where members spent their time during the week.

Warren described Saddleback's programme for "spiritual growth", with numbered headings. Spiritual growth, he explained, was (1) a lifelong process, (2) measured by obedience, (3) based on God's word and (4) would set me free. Free from what? From habits, hurts and hang-ups, from painful memories, worry, bitterness and guilt. How would I achieve that? According to Warren, Jesus had the plan. At Saddleback, he assured us, we would learn to follow his plan "systematically, sequentially and in a process" through the classes Saddleback offered.

This is the future of middle-class US Christianity, according to the latest American Religious Identification Survey (Aris). If the trend identified in the Aris study continues, we will see a country divided between conservative evangelical Christians and secular liberals – the latter hostile to religious belief, identified with evangelical Christianity. This is bad news because popular evangelical Christianity is religiously vacuous. It is directed to secular ends which, arguably, should be promoted by secular means. Saddleback is religion for people who don't like religion: transcendence is not on the menu.

Although almost half of Americans say they have had a religious experience, mysticism is likely a recondite taste. For the minority who have that taste – who seek God as an object of contemplation – Saddleback has nothing. Evangelical and mainline churches promote activism and are contemptuous of navel-gazing.

As a navel-gazer, I was depressed by Saddleback. It seemed the butt end of Christianity: stripped of history and icon­ography, wholly immersed in its secular surroundings, constructed according to a business model and promoted by motivational speakers – bland, cheerful, dull.

We drove away, past immaculate housing estates and strip malls iterating chain restaurants and shops, replicated in every suburb from coast to coast. I wondered why anyone would want to live in that charmless place, much less to get more of the same at church.