WASHINGTON -- The next speaker blew into town like a tornado, upending the customs of conduct in the Capitol, forcing whole political structures to collapse of their own weight, spewing rubble in all directions, raining destruction on the social conventions and political habits that have animated the House of Representatives for four decades. Newt Gingrich is a new and different force in Washington.

New, different -- and misunderstood in a fundamental way. His is not the ascendancy of devout conservatism in the tradition of William McKinley or Robert Taft or even Barry Goldwater or Ronald Reagan. This is a conservatism with a different kind of energy, power and potential. This is a conservatism born of frustration with the mainstream of the 20th century but shaped to the world of the 21st century.

The defining difference about Newt Gingrich is this: Like most of his conservative forebears, he is anti-government. But, unlike almost all of them, he is not pro-big business.

That is no small thing. It means that, under Gingrich, the Republican Party has its first authentic opportunity to separate itself from the image that, since the age of Franklin D. Roosevelt, has prevented it from becoming the majority party. Reagan spoke from the heart of a party and a conservative movement that reached ordinary citizens and small business, but his head (and, more important, his government) was the servant of big business.

Lost in the whirl of controversy and upheaval here in the last several weeks is the discomfort that many of the nation's signature businesses feel about the advent of Gingrich. To be sure, the new speaker of the House favors a reduction in the tax on capital gains that those businesses have trumpeted for a dozen years, but he also represents a threat to the way they have done business for generations.

Indeed, Gingrich's relationship with business provides one of the clearest windows into his political, social and cultural philosophy. And though his ascent has driven a wedge throughout Washington, nowhere are the splits greater than in the business community.

Many in the Gingrich circle offer no comfort to big business in the new era. ''Besides the old Congress, the single most out-of-touch group in America are the CEOs of Fortune 500 companies,'' says Frank Luntz, the Republican pollster with ties to Gingrich. ''They don't have a clue.''

Gingrich is attuned to the information-technology industries, to any sector of the economy where there remains room for entrepreneurship, to insurgent businesses that want to sweep away the old ways of doing things in much the same way the new speaker has, before even taking office, transformed not only the Capitol building but the entire capital.

The new speaker's populist roots make him instinctively suspicious of large institutions of any kind. ''Gingrich comes from revolution,'' says Fred Wertheimer, the president of Common Cause, the self-styled citizens' lobby, ''and corporate America is not about revolution.''

For that reason, the Bell operating companies, many of the restaurant and food-service divisions of Pepsico and scores of entrepreneurial computer and software companies will have the ear of Gingrich, while the Big Three automakers, the big steelmakers, the large computer hardware companies and the chemical companies -- some of which have contributed to various Gingrich causes over the years -- are in danger of being shut out.

The splits even affect individual industries. For example, the companies associated with the American Electronics Association may have little truck with the new Republicans -- the companies' leadership is regarded as relatively staid, too quick to accommodate, not revolutionary enough -- while the companies associated with the Electronic Industries Association -- regarded as more entrepreneurial by the Gingrich circle -- may get a better a hearing.

But the skepticism doesn't flow in only one direction. Many of the leading US chief executive officers favor reducing the tax on capital gains but are exceedingly wary of Gingrich's zeal to reduce taxes in general. These business leaders are, above all, worried about the deficit, which affects bond prices and the financial markets. The leaders of many of the smaller, more entrepreneurial businesses don't worry about the bond market because in large measure they don't float bonds; they want tax cuts because lower taxes spur people to spend more money.

Executives of big corporations also worry that less federal spending will put pressure on states to increase their taxes, shifting the tax burden from Washington to the states. The cost of doing business in some states would rise, giving some companies relative advantages but penalizing others. Companies in the Frost Belt would be hurt, and those in the Sun Belt would be helped. But large corporations would rather not have such imbalances, because they find it awkward, inconvenient and expensive to shift their resources.

''Their priorities are so different from those of the average American that it's almost sad how great the disconnect is,'' Luntz says. ''Newt wants to help the small-business person, because that's where the future lies. The new technologies and techniques are almost entirely being developed by the small businesses. It's the teams of three or four people who are winning the future, not big business.''

Some of the motivation for Gingrich's preference for smaller, entrepreneurial businesses is philosophical, of course. But some of it is cultural.

The anvil of his views toward business in the capital was the tax accord of 1990, long reviled by conservatives because some Republicans and a GOP president, George Bush, acceded to tax increases as a tool to reduce the federal budget deficit.

On one side of this agreement were Washington corporate representatives, epitomized by the Business Roundtable and leading US businesses, all desperately wanting to reduce the deficit even if it meant raising taxes. Gingrich heavily weighted himself against them and toward the small- business groups. The smaller businesses were more worried about take-home pay, concerned that any diminution there would hurt their enterprises.

That sealed Gingrich's connections with the National Federation of Independent Business, regarded as the premier representative in the capital of small businesses, and other Washington trade groups such as the National Association of Wholesaler-Distributors. Gingrich learned in 1990 which groups had grass-roots organizations and which had only a battalion of fancy lobbyists with good tennis backhands and memberships in tony golf clubs.

''I don't think the man has any of those social hobbies,'' says Benjamin Y. Cooper, senior vice president of the Printing Industries of America, one of the groups with close ties to Gingrich. ''He is not that kind of Washington figure.''

Gingrich grew to have contempt for many of the companies that maintained Washington representatives, believing that they stood in the way of his rise or at best contributed both to Republicans and Democrats. He delights, in fact, in challenging trade group lobbyists face-to-face, and for many years had frosty relations even with the US Chamber of Commerce. Many of these corporate representatives, of course, are former Democratic lawmakers or congressional staff members. They have no interest in seeing Gingrich succeed.

For that reason, for example, the Gingrich wing of the GOP is wary of the National Association of Manufacturers, which had grown accustomed to being one of the most influential business groups in Washington. The group may be well- positioned politically, and its legislative goals increasingly are being brought in line with those of the new GOP, but many in the Gingrich network know that Jerry Jasinowski, president of the group, is marked by original sin: He served as assistant secretary of commerce in the Carter administration.

Much of what Gingrich has done in the weeks leading up to becoming speaker can be explained in terms of his antipathy to the status quo. Last week, he and his associates abruptly pulled the plug on 28 caucuses in the House, including the Congressional Steel Caucus, the Congressional Automotive Caucus and the Northeast-Midwest Congressional Coalition.

Part of Gingrich's motivation, of course, was his determination to pare the size of government. But part of it was a desire to change the architecture of political life on Capitol Hill and thus to frustrate lobbyists who had grown accustomed to the 28 caucuses and had found ways to bend them to their own interests.

The new speaker's determination to wrest control of the legislative process from Washington's lobbyists can be seen just below the surface of a number of his other moves. Restructuring House committees and altering the names and responsibilities of some time-honored panels severs longstanding ties between lawmakers and lobbyists. Similarly, his decision to make legislation easier to amend on the floor takes away a long-cherished prerogative of committee chairmen, who often took their lead -- and, in some cases, the actual legislative language -- directly from the ''Gucci Gulch'' of big-business lobbyists.

Gingrich is in many ways a mysterious figure; in his introduction to Alvin and Heidi Toffler's book ''Creating a New Civilization: The Politics of the Third Wave,'' Gingrich speaks easily of the Renaissance, the collapse of Confucian China and even the fall of the Japanese Liberal Democratic Party. ''What seems to us, looking back in history, a brilliant, exciting period of innovation seemed to its contemporaries a terrifying collapse of the existing order,'' he writes.

Those who seek to fathom his mind must remember that the Georgia representative considers himself a revolutionary. He takes glee in blowing up the status quo -- and he believes that in many ways big business in the United States has learned to live with, even profit from, the status quo.

For all their public criticism of federal regulation, many big businesses -- slaves to stability and certainty, in the view of the Gingrich group -- have grown used to regulation, and some have actually grown cozy with regulators. In any case, they have legal affairs departments and teams of accountants that can steer them through the regulatory maze. Smaller businesses do not. They want to repeal regulations, or at least to rein them in substantially.

In truth, small businesses have been with Gingrich from the start, providing him with money and with the foot soldiers of his army of occupation that just now is settling into Washington. He has learned over the years that if he helped a big company there was little political payoff, but that if he helped a bunch of small businesses they would notice it, appreciate it and remember it. In the end, Gingrich, like business itself, is motivated above all by the most ancient tenet of the financial world: self-interest.