On the morning of Aug. 23 last year, President Bush and his national security adviser, Brent Scowcroft, went fishing for bluefish in the Atlantic near the president's vacation home in Kennebunkport, Maine. They returned to shore four hours later with three fish and a foreign policy concept that would dominate Bush's rhetoric for months: the quest for a "new world order."

Scowcroft had suggested the long fishing expedition to talk over all aspects of the three-week-old Iraqi invasion of Kuwait. As the former Air Force general described it later, the "searching discussion" went well beyond immediate U.S. options to "the broader ramifications of what we were doing and what it might mean."

The United States and Soviet Union -- at odds on most international issues for decades -- had issued a joint declaration opposing the invasion. In the United Nations, the two big powers, along with the three other permanent members of the Security Council, Britain, China and France, were working together to reverse Iraq's military action. With the main players in world politics cooperating instead of confronting one another, Bush and Scowcroft concluded there was a chance for the first time since World War II for the international system as a whole to function as a barrier to aggression.

"We believe we are creating the beginning of a new world order coming out of the collapse of the U.S.-Soviet antagonisms," Scowcroft said later that day. "We want to use the crisis to build support around the world that the behavior of Saddam {Hussein} and the Iraqis is unacceptable. If we can do that, it could be very, very important as we look to the future. . . . We're trying to build an order beyond this crisis."

The Bush administration's embrace of a "new world order," which began on that sunny August day, has touched off intense speculation at home and abroad about U.S. policy in the post-Cold War world.

Many foreign policy experts have ridiculed the concept, while others have questioned what it is all about. The latest edition of the Bulletin of the Atomic Scientists contains articles by 17 international policy experts speculating on it, with an editorial calling it "a bold stroke that could retake the slogan-making turf for the Republicans who, thanks to Ronald Reagan and associates, already dominate the hotly contested public manipulation field."

The Bush White House originally adopted "beyond containment" as its foreign policy watchword in 1989, switching last August to "new world order." In recent weeks, however, the official use of that phrase has declined sharply, and officials expressed concern that far too much has been read into it. Several attempts to define it broke down, and a number of officials admitted they are unsure just what it means.

Bush actually had spoken of a "new world order" at least once before, in a February 1990 political speech hailing the crumbling of the Iron Curtain the year before. By Aug. 30, the phrase became a central feature of Bush's public oratory, including an address to the U.N. General Assembly and three speeches to joint sessions of Congress. According to a search of presidential documents published by the White House, Bush referred publicly to a "new world order" at least 42 times from last summer to the end of March.

In an April 13 speech in Montgomery, Ala., Bush gave what he said would be the first of a series of speeches describing in detail the chances for "a new world order emerging after the Cold War." But that speech addressed the subject in only very general terms, and the next speeches skirted the subject as the White House encountered difficulty in defining the concept. The latest word from presidential aides is that a Bush address next Wednesday in Colorado Springs will deal with the new world order as applied to U.S. military policy and arms control in the Middle East.

The arguments over the meaning of the new world order are part of the struggle to redefine U.S. foreign policy in an era when the world has changed in fundamental ways, politically as well as militarily. But so far, no Bush doctrine or summary statement seems to capture the new aims of U.S. policy.

New York Times columnist William Safire traced the new world order concept back to Alfred Lord Tennyson's 1842 poem about the death of King Arthur, where he wrote, "The old order changeth, yielding place to new." The phrase "new world order" was used occasionally in the 1980s, notably in Soviet President Mikhail Gorbachev's address to the U.N. General Assembly in December 1988.

Scowcroft has been openly embarrassed about all the attention and different interpretations of the phrase. Recently he complained that it was just a "catch phrase" that had become endowed with grandiose meanings beyond anything he or Bush originally conceived.

In the April 13 speech, Bush said the new world order "refers to new ways of working with other nations to deter aggression and to achieve stability, to achieve prosperity and, above all, to achieve peace." With new world threats emerging, he said, it is "a challenge to keep the dangers of disorder at bay." He added that "the new world order really is a tool for addressing a new world of possibilities. This order gains its mission and shape not just from shared interests but from shared ideals."

Whatever the new world order is, the administration has not formulated specific plans or policies for bringing it to fruition. Several officials said the concept is rarely, if ever, discussed in policy meetings.

"We've heard less about the new world order since the {gulf} war was over," said Rep. Lee H. Hamilton (D-Ind.), a prominent legislator on foreign policy issues, suggesting that Bush used it in part to buttress support for the international effort he organized against Iraq. "It may be more of a rallying cry than a description of the world. I think it's premature to suggest we will have a big change in the world" under present circumstances, Hamilton added.

Former secretary of state Henry A. Kissinger, writing in The Washington Post, said the concept arose from the need of Americans to find grand justifications for fighting wars. Comparing it to President Woodrow Wilson's failed effort to replace balance of power with worldwide opposition to wrongdoing on the basis of morality, Kissinger wrote that "the new world order cannot possibly fulfill the idealistic expectations" expressed by Bush.

John Lewis Gaddis, a professor at Ohio University and a historian of the contemporary era, expressed doubt about a new world order, saying that "you really can't talk it until you talk about new world problems" such as the disintegration of existing nations, including the Soviet Union, India, Iraq and Yugoslavia.

"The administration hasn't fully diagnosed the causes of disorder. We're beginning to see that the use of military force in the gulf, for example, did not solve the problem of the Kurds, the future shape of Iraq or even the future of Saddam Hussein," said Gaddis.

The author of "The Long Peace," which depicted the Cold War as an era of unusual stability in international affairs, Gaddis said the new era "ain't going to be orderly."

Bush, in his many and varied remarks on the subject in recent months, applied new world order language to many different situations. Among other things, he said the "new world order" must include the peaceful resolution of the division of Lebanon (Sept. 24), that it was signaled by the signing of the treaty limiting conventional arms in Europe (Nov. 19), that it offers a much better chance for peace in the Middle East (Nov. 23) and that it depends to an important degree on China's cooperation in the U.N. Security Council (Feb. 6).

The most consistent theme in the remarks of Bush and senior administration officials is that of an expanded role for the United Nations.

Thomas Pickering, the U.S. ambassador to the United Nations, defined the new world order as "using the United Nations and Security Council in regional disputes" and said this is part of "a long progression of change" that began before the gulf war and accelerated in its wake.

"Five or six years ago . . . it was a rare issue on which you broke free" of deadlock, said Pickering.

The U.N. ambassadors of the five permanent members (nicknamed the Perm Five) of the Security Council have become a close-knit club, holding frequent informal meetings to work on major problems. From Aug. 1 to Nov. 1, when the question of international action against Iraq was under intense discussion, the Perm Five ambassadors met 68 times, more than once for each weekday in the entire period.

Reflecting the new great-power emphasis, the crush of business for the previously sleepy United Nations includes emergency refugee relief in Iraq, elections in the Western Sahara and Angola, peace plans for Afghanistan and Cambodia and nine peace-keeping operations, mostly in old hot spots around the globe.

Despite its verbal support of the United Nations, the United States is also among the world body's greatest headaches. Since Moscow began backing U.N. actions and paying its dues promptly several years ago, the United States has become the organization's main deadbeat, owing $717 million of the $1.02 billion in arrearages the world body has been unable to collect to support its expanded activities in the era of the "new world order."

Staff writer Dan Balz contributed to this report.