Pat Buchanan's new book, "Day of Reckoning," is a tour de force, expanding on and combining the arguments and evidence he presented in three previous books ("The Great Betrayal," "A Republic, Not an Empire" and "State of Emergency") to make a powerful case that free trade, multiculturalism and imperial overreach threaten to put America on the dustheap of history.

As my friend always does in his books, brother Patrick combines shrewd analysis and his own crisp and passionate words with wonderful quotes from others. He quotes George Orwell's observation that "ideology animates 'the streamlined men who think in slogans and talk in bullets.'" That description remains as fresh as this evening's cable political talk shows and news reports.

I cite that quote because, for me, one of the strongest elements in "Day of Reckoning" is Buchanan's remorseless assault on ideology -- whether being used by imperialists, free traders or cultural manipulators. This may sound surprising to some because these days, many people both on the left and right proudly support their respective ideologies.

But like Buchanan, I was educated in an age when conservatives proudly asserted that conservatism was, by definition, the absence of ideology. Ideology was -- and remains -- the product of intellectuals who substitute for the wisdom of the ages, the organic unfolding of their institutions, the teachings of their faith and common sense their own fanatical belief that their ideas can (in Russell Kirk's words) convert our world "into a terrestrial paradise through the operation of positive law and positive planning."

Or as Pat writes: "Ideology has one foot grounded in reality, but the other is ever on quicksand. For no one can know the future. Yet the True Believer has moral certitude, for his ideology foretells a future certain to come if the sacrifices are sufficient and the anointed leaders are faithfully followed."

And with that bit in his teeth, Pat runs riot through the ideologies of free trade, Bushian wars-for-democracy arguments and open borders theories. It is not only honest, solid historic reporting but also splendid, angry prose.

Although by both instinct and experience Pat Buchanan is a respecter of presidents, incapable of public rudeness to an American president, in this book, Pat barely disguises his contempt for the sometimes-foolish ideological words of President Bush -- which he quotes often (and in context) to the detriment of the president.

For instance, he quotes the president: "Governments accountable to their people do not attack each other." An exasperated Buchanan follows with: "This may come as a surprise to descendants of those who fought for Southern independence. Does Bush think Mr. Lincoln's Union or the Confederate States of America were not accountable to their people? Democratic Israel bombed democratic Lebanon. In 1914, the most democratic nations in Europe plunged into the bloodiest war in history. Democratic peoples are not immune to blood lust."

Pat always has written with passion, but in this book, there is a palpable anger at a president he believes has done terrible damage to America. He quotes President Bush: "Freedom is the design of our Maker and the longing of every soul. Freedom is the dream of every person in every nation in every age." Pat responds with uncharacteristic sarcasm: "One wonders: Who writes this, and does the president read it before delivery? Again, did Lenin, Stalin, Hitler, Mussolini, Mao, Fidel, Uncle Ho and Pol Pot long for freedom in their souls?"

For anyone who can't put his anger or frustration with President Bush into words: Read this book. Because Pat gives you the words, the passion, the argument and the evidence to support your feelings.

But even if, like me, you are generally supportive of President Bush, this book will challenge you fairly to defend your views. Certainly his case that the ideology of free trade is contradicted by both history and current evidence is not easily dismissed. As I argued in this space last week, it is time to have a major, nonideological, practical national debate about free trade. Of course, his position about controlling illegal immigration, which he championed long before it was popular, now has gained clear majority support in the country -- in measurable part because of his leadership through the years.

Where I disagree with Pat most strongly in this book (and with which I will deal in my next book, to be published in the summer) is his assertion that America can best protect itself by broadly withdrawing from the world, bringing our troops home from almost everywhere and letting the world unfold without our active intervention and management.

Nonetheless, 15 years ago, Pat was dismissed as a paleoconservative at the margin of American politics. It is a tribute to the power of his words and ideas -- exemplified by and reaching climax in "Day of Reckoning" -- that he now may well be pointing the way to the future policy of the American people and their government.