American Theocracy: The Peril and Politics of Radical Religion, Oil, and Borrowed Money in the 21st Century. By Kevin Phillips. Viking, 462 pp., illustrated

Just over a century ago, Henry Adams's younger brother Brooks published a number of bold if idiosyncratic books speculating on the course of world history. They were not purely academic exercises, for Adams kept one eye always on the question of America's future. He thought the United States would dominate the 20th century, and celebrated that prospect. But it also worried him.

His theory was that any given civilization was, literally, a bundle of energy that waxed and waned over time. How a society managed its energy level was a function, in part, of the two basic human emotions, identified by Adams as Greed and Fear. Phases of greed led to increasing urbanization, commercial activity, and skepticism. This increased the overall level of energy, but only at the risk of subjecting it to a rather one-dimensional development. Gaining the world and losing the soul -- that sort of thing.

By contrast, a society with a low or decreasing energy level would be characterized by fear, since it was less able to subject the world to its control. If an age of greed culminated in domination by financiers, the natural leaders in a period of fear were religious authorities. The rise and fall of empires, for Adams, was a protracted struggle between the forces of greed and fear -- with shifts of energy level being moments of crisis, when one or the other takes over.

While his ideas still hold a certain fascination for specialists in the history of American thought, it is safe to say that very few people nowadays could be described as followers of Adams. One important exception to that rule is Kevin Phillips, who first came to prominence as the architect of Richard Nixon's ''Southern strategy" for realigning support for the Republican Party.

Phillips's new book, 'American Theocracy, will naturally be taken as the latest in a series of criticisms of the course of the GOP over the past 20 years. But it is also as pure an application of Adams's theories as anything published in the past several decades.

It is not just a matter of some vague resemblance -- as there is between, say, Adams's ideas and Oswald Spengler's ''Decline of the West." Rather, you actually need to keep the old Brahmin's outlook in mind while reading ''American Theocracy," or else it will look like a set of miscellaneous reading notes and anti-Bush editorials cobbled together into a stimulating but chaotic book with a somewhat misleading title.

To the naked eye, American Theocracy looks like three distinct projects jostling one another between hard covers. The first of them is a study in petro-politics in the United States, with special emphasis on the emergence of ''the new national party politics of oil" during the 20th century. Phillips is the kind of tough-minded realist who doesn't even bother to feign shock at the idea that our foreign policy has a bottom line. When Dick Cheney said in 1999 that ''by 2010 we will need on the order of an additional fifty million barrels a day," certain geopolitical consequences followed. Why pretend otherwise?

The second section -- the portion stressed by the book's title, seemingly geared to catch the eye of irritated Democrats in a hurry -- is an account of the rise and consolidation of the fundamentalist voting bloc and the transformation of the GOP into God's Own Party.

Much of the material on apocalyptic doctrine and the growth of the evangelical subculture is drawn from work by sociologists and religious historians. But Phillips is really in his element while sorting through the demographic data. He traces ''the piggybacked extension of southern culture and evangelical, fundamentalist, and Pentecostal religion" throughout the United States to the migration of whites from Dixie -- pulled to the north and the west, in large part, by ''the buildup of military bases and war industries." The transformation of the South from a solidly Democratic region into a Republican stronghold (per Phillips's own strategy almost 40 years ago) has had the reciprocal and unintentional effect that he calls ''the southernization of U.S. politics and the growing, glaring reorganization of the Republican party around religion."

In the final section, Phillips considers the ''financialization" of the United States: the process, that is, ''whereby financial services, broadly construed, take over the dominant economic, cultural, and political role in a national economy." He calls the past quarter century ''a triumph of financial-sector protection over market comeuppance" and provides a survey of how the Federal Reserve and the Treasury Department have repeatedly bailed out banks, important currencies, and hedge funds -- even as the financial-services industry enjoyed the benefits of deregulation.

Taken in pieces, Phillips's analysis sounds like a vaguely Michael Moore-ish indictment of the present course of the ship of state. But how the parts fit together is not always clear.

The key, I think, comes in a passing reference by Phillips to Adams (who was admired by Teddy Roosevelt, as well as an influence on the old isolationist wing of the Republican Party). The three sections of 'merican Theocracy, covering oil, apocalyptic religion, and the corrupting effects of ''the borrower-industrial complex," correspond very neatly to the three core ideas in Adams's theory -- namely, energy, fear, and greed.

Between the lines, you hear the same worried conclusion that Adams reached: The forces that drive a civilization's expansion may culminate in its disintegration. And then another bundle of energy may begin its ascent, elsewhere in the world -- perhaps in the Pacific region. As Phillips puts it, in glum understatement: ''China's early history of innovations in hydraulics, natural-gas use, and deep drilling may be relevant."