THE GENIUS OF AMERICA: How the Constitution Saved Our Country and Why It Can Do So Again, by Eric Lane and Michael Oreskes. Bloomsbury, 256 pp.

A MORE PERFECT CONSTITUTION: 23 Proposals to Revitalize Our Constitution and Make America a Fairer Country, by Larry J. Sabato. Walker and Company, 352 pp.

UNRULY AMERICANS AND THE ORIGINS OF THE CONSTITUTION, by Woody Holton. Hill and Wang, 370 pp.

It was 220 years ago this summer that a convention met in Philadelphia to draw up what would become the Constitution of the United States of America. Our sense of historical memory is cued to public celebration of such moments when we come to the big, round intervals - centennials, for example. But now we have three new, well-publicized books on the Constitution showing up as if to mark a special occasion. Perhaps it is coincidence. This is a perennial topic, after all. Even the nonlegal overtones of the word "constitution" give some indication that we are talking about something beyond the document itself.

One sense is very subtle. Philosophers sometimes speak of the "constitution" of a particular thing in the world (an individual's sense of identity, for example) out of universal categories (space, time, number). On the other, we have the much less abstract notion invoked in ordinary speech, as when we refer to fiber being "good for your constitution." When we discuss the structure created in Philadelphia, it's often with both senses at least partly in mind. The Constitution is part of the infrastructure of American identity - but it's also how we digest experience.

And so we might be particularly inclined to notice its 220th anniversary if recent circumstances were raising questions about the state of our constitution, metaphysical and otherwise. The three books under review respond in very different ways to this prompting.

By far the sunniest in sentiment is The Genius of America by Eric Lane, a law professor at Hofstra University, and Michael Oreskes, executive editor of the International Herald Tribune. The authors sketch the historical background of the Constitution, treating it as a kind of compromise between the fiery democratic passions of Thomas Paine and the cooler, more tough-minded sensibility of James Madison.

Later revolutionaries - starting with the French in 1789, a few months after the U.S. Constitution was ratified - tried to use state power to reorganize society. Not so the Americans. "To the Framers," the authors write, "the better world, which they believed would come, was a byproduct of their government, not its purpose. The citizens would decide in common what that better life entailed.... They elevated process over result."

The Constitution was flexible and open-ended - a device so brilliantly designed, so adaptable to changing circumstances, that it could eventually open up the category of "We the People" to include those who had been slaves when it was drafted, and then women. According to The Genius of America, the Constitution was designed to foster a deliberative process that is - as much as majority rule - essential to democracy. The framers "believed that action without consensus was far more dangerous than stasis while reaching for consensus."

If people are frustrated with the political process now, that reflects the waning of what the authors call our "Constitutional Conscience" - a respect not only for the mechanisms of governance but the process of deliberation. And that decline in turn follows from a general and rather profound ignorance. The written Constitution is just fine. But our spiritual constitution evidently needs a better diet than it has been getting.

"We take our democracy for granted," write Lane and Oreskes, "because we don't understand how hard it was to build it, how much courage (not just on the battlefield) it took to preserve it, and how close it came to failure on several occasions, from the alien and sedition acts, through the Civil War to the Great Depression." What we need, then, is a kind of nationwide remedial civics class - which is actually a pretty fair definition of what the authors have tried to conduct.

Larry J. Sabato's A More Perfect Constitution is more skeptical about just how adequate the inherited constitutional framework is now. The author heads a political think-tank based at the University of Virginia and has some profile as a media commentator. His book has a quality somewhere between that of a manifesto and press release. It outlines a series of major overhauls that would improve the workings of American civil society, and calls for a new Constitutional Convention (per Article V of the Constitution we now have) to realize them.

The gist of Sabato's complaint seems just. The mechanisms of representative democracy established in a largely rural country with a small population are not simply out-of-date but profoundly unrepresentative now. Thanks to an influence in the Senate that is disproportionate to their small populations, some states are able to channel billions of dollars away from parts of the country with much larger populations and greater needs. (This means you, Wyoming.)

Thus, the Senate ought to be expanded by giving the 25 most populous states additional representatives; plus we should give seats to former presidents and vice presidents, who would be given the title "National Senator." There ought be compulsory national service for all young people. The president's term should be set at six years, with "the option to request a two-year extension, so that he or she would potentially serve the same eight-year tenure as currently." And we should keep the Electoral College, while changing it in various ways.

If I am hazy on that part, it's because I kept thinking of a catchphrase some bloggers use whenever political discussion wanders off into the drawing of hypothetical blueprints: "Also, everyone should get a pony." Sabato has planted his flag between wonkery and daydreaming.

Even if you think that many of his proposals are sensible, or at least worth discussing - and I do - there is something pervasively unreal about A More Perfect Constitution. Sabato is, in effect making an argument exactly opposite that of "The Genius of America." He holds that the Constitution as founding document is showing its age, but that "We the People" are fundamentally healthy.

Finally, we have Woody Holton's Unruly Americans and the Origins of the Constitution, a book working on a very different level from the other two. An assistant professor of history at the University of Richmond, Holton digs much deeper into the ideas and debates of the 1780s than do the authors of The Genius of America. Less preoccupied than Sabato with 21st century problems, he leaves the reader with a rich sense of how profoundly the Constitution reflects the troubles of a pre-industrial society.

The parts of the Constitution that Americans value most (freedom of speech, for example) tend to come from the later amendments called the Bill of Rights, while the basic concept of representative democracy was already found in the "Articles of Confederation" that provided the framework for the early Republic. What the convention of 1787 created was a structure of checks and balances that centralized government while limiting its power.

This much we all remember from high school, or should. But as Holton shows, the resulting system was not simply deduced from abstract principles. It was designed to limit the power of small, impoverished farmers to press for debt relief - a tendency that would then, in turn, make foreign investors steer clear of the risky American market.

The idea that the Constitution was shaped by such bottom-line motivations is not new to historians; they have debated it for almost a century now. But it's still largely ignored by celebrations of the Founding Fathers such as The Genius of America. At a time when arguments over the Constitution are often framed in terms of "original intent," a book like Holton's poses valuable questions about just how timeless and selfless that intent may have been.

"While there is no reason to question [the framers'] claim that they hoped to benefit all free Americans," writes Holton, "what they meant to give the ordinary citizen was prosperity, not power." And to that degree, it for the most part succeeded.

Whether our constitution (in any sense) would long survive another economic crisis is a different question, of course. And chances are we will find out one way or another between now and the 250th anniversary of that gathering in Philadelphia.