For half a century and more, theirs has been a delicate, occasionally fractious relationship. Fluctuating according to the circumstances of the moment, between liking and hating, but marked most often in recent years by studied mutual indifference. You go about your business; we'll attend to ours.

Many New Yorkers who, with irksome frequency, must battle the inconveniences and the aggravations that the presence of this prissy Felix of diplomacy generates in a city of Oscar sports freaks may wonder today whose bright idea it was to inflict the international organization on them in the first place. Was it some deluded, nearsighted, power-hungry leader unwilling or unable to foresee the disruptions the UN was sure to cause, not to mention the cost to the taxpayers?

Folks, it was one of yours: William O'Dwyer, New York's mayor back in 1948. He moved heaven and earth to have the UN locate in Manhattan after the decision had been made to keep the organization in the United States.

It had been occupying temporary quarters on Long Island and was looking for a permanent home. In that heady, innocent time of huge enthusiasm for this new experiment in global togetherness- created, as the UN Charter dictated, to avoid "the scourge of war" that had decimated two generations--competition among cities to host the UN was intense.

With the selectors zeroing in on the City of Brotherly Love, Philadelphia (how appropriate to the times), and only a few days left until the UN General Assembly was to make the fateful selection, O'Dwyer and the philanthropic Rockefellers between them pulled off a coup for Manhattan. The US government put up $65 million as an interest-free loan to build a headquarters on the East Side, on land that was being used by slaughterhouses. In today's cheaper dollars, Washington's largesse was the equivalent of more than $500 million.

San Francisco, where the Charter was signed on June 26, 1945, was an obvious contender, but in a Eurocentric era was deemed too distant. St. Louis, another possibility, was perhaps too central, too much a part of the isolationist-prone American heartland. (The adjournment of the annual session of the 50-member General Assembly in that bygone, pre-jet age was the date of departure of the last of the Cunard liners guaranteed to carry passengers to Cherbourg and Southampton in time to celebrate Christmas.) A principal motivation for preferring the US as the UN's home, instead of, for example, Geneva, where the League of Nations settled after the Great War, was the hope of preventing a repeat of the fate that befell that body. In part for lack of US political support and participation, that first international peace organization failed woefully to discharge its mission of sparing humankind from the second devastating conflict that began in earnest in September 1939 after previews in Spain and Ethiopia. But all of this is history. The UN on one side and the US and the City of New York on the other have had their political and emotional ups and downs together over the past almost 57 years. Aside from a simmering resentment never far beneath the surface among some elements in Manhattan, 2002 began what bids fair to be one of the up periods.

Secretary General Kofi A. Annan has high hopes for great relations with Michael R. Bloomberg, who, seconds after midnight on Jan. 1, was sworn in as the city's 108th mayor, and President George W. Bush today is perceived, by people at the UN, to be a friendlier figure than was feared during his initial unilateralist tear. All of this, of course, can quickly change. Alarm bells are already ringing in the capitals of several UN member states, as well as in their New York diplomatic missions, in worried reaction to the Bush bellicosity in that recent "axis of evil" speech on the State of the Union that named Iraq, Iran and the Democratic Republic of Korea as countries the US might eventually have to do something serious about in order to force them to shape up. Shades of Ronald Reagan, a conservative former president, who scared the pro-Moscow nonaligned nations with his talk of the Soviet "evil empire."

Now the UN is on tenterhooks lest the Bush administration, at the urging of hawks like Donald Rumsfeld and Paul Wolfowitz, follow through with an offensive against Iraq's Saddam Hussein, the leading villain in the declared axis. Kofi Annan has stated several times since Sept. 11 that US military action against Baghdad would be disastrous. In the Security Council, discussions are still under way in hopes of getting Saddam to permit UN weapons inspectors to go back to work in Iraq, perhaps in a quid pro quo for modifying the current sanctions regime, the effects of which are seen to be inhumanely harsh on a powerless civilian population, especially on women, children and the sick and aged. The inspectors, last led by the Australian Richard Butler, a major doubter of Saddam's good intentions, were ejected in December 1998. Butler, now working for the Council on Foreign Relations, and some other international experts within and outside the UN believe that the 40-month hiatus in monitoring may have been used by Saddam to rebuild Iraq's arsenals for mass destruction. Charles Lichtenstein, a member of the Reagan-era team at the UN, was the first American delegate there ever to say publicly that maybe the world body was in the wrong place. Angered by many members' disapproval of US policies--as some vocal followers of George W. Bush are here in 2002--and especially (as now) policies related to the Middle East, Lichtenstein wondered out loud whether the UN might like to pack up and leave New York. If so, he said, he and a host of fellow dry-eyed citizens would be at the pier "to bid a fond farewell."

Spoken mainly in jest--or so its hearers hoped--the idea still was not original. Earlier in UN history, an incorrigible representative of Saudi Arabia, one Jamil M. Baroody, often ranted on about a politically inhospitable New York environment, what he perceived as the unhealthy influence of Jews in politics and the media, and his belief that the time had come to look for new quarters and ship out. Baroody, nominally Christian and not a Saudi by birth, was never, therefore, given a permanent representative's rank and was treated by his colleagues as a bit of a clown. In fact he was a highly intelligent diplomat versed in politics and history, though unquestionably eccentric. There were doubts whether his masters in Ryadh always knew what their prolix envoy was up to. (His role in confusing the debate that led to the UN's ousting of the Taiwan delegation and recognizing the People's Republic of China is a story for another time.)

In truth, relations between the US and the UN and between the organization and the host city have suffered through plenty of strains. But neither the UN nor the city has even been known to have thought seriously about a breakup.

Today, the world body's firmly positive response to the events of 9/11 and repeated declarations of support for the campaign against terrorism--a welcome surprise to many Americans, considering the hostility felt in the UN toward the US over its policies toward Israel and the Palestinians--can only strengthen the ties that bind.

This warmer mutual feeling will continue, it's widely believed, so long as the UN stays on track in the US-led struggle against the evil of terrorism and other member states resist the temptation to waver while memories of that tragic Tuesday begin to fade and appeals grow more insistent, especially by concerned developing countries, for equal time for other important items on the international agenda. Their call has been echoed with an increasing sense of urgency in recent weeks in statements by Secretary General Annan.

The arrival of the new mayor of New York, meanwhile, is hailed as a major event that will be significantly helpful to an organization that sympathizes with the immense problems he faces because it has only lately come out of its own prolonged rough passage. Still, the caution flag is up--against setting expectations unrealistically high.

Annan professes to have received "warm expressions of support from Mayor Bloomberg"--meaning support for the UN, not for the Secretary General. If so, those kind words cannot have been reported prominently because few are traceable. Perhaps these were whispers in Annan's ear or private utterances rather than public pronouncements?

Last year's terrorist attacks left this city gravely damaged and with more serious matters on its mind than the maintenance of cordial relations with an alien entity in its midst that includes "rogue states" considered to be a threat and whose possible intentions alarm the Bush administration, as they did the Clinton White House. One may wonder whether the UN is much on City Hall's radar, except when the organization's needs for security come up -and funds must be found to meet them.

A senior aide of Annan's who was asked about the high hopes around the executive office for closer contacts with Bloomberg, after the cooler winds that blew out of City Hall during much of the reign of Mayor Giuliani, came up with the rather lame response that the new mayor once vouchsafed that his early ambition was to be UN Secretary General.

Apparently this factoid has been seized upon as a sign of an enduring friendship for the organization. "His heart is in the right place," the aide added.

A month after his swearing in, Bloomberg did supply positive evidence of what may indeed be his good feelings for an organization estimated to be worth more than $3 billion a year to the city and its suburbs, through goods and services purchased, rents paid and thousands of commercial transactions, including all those lunches and dinners at two- and three-star restaurants. The gesture of mayoral goodwill came in the appointment of his younger sister, Marjorie Tiven, a Columbia University graduate in social studies, to be New York City Commissioner for the United Nations and Consular Corps. Tiven is an authority on problems of the aging and, by happy coincidence, 2002 is the UN-designated International Year of the Aging, which will be highlighted at a conference in Madrid in May under the world body's auspices. The UN post in city government, in which Tiven will serve for $1 a year--the Mayor is forgoing his own $195,000 salary--is more significant than it may sound. The Commission Tiven leads is a valuable lifeline for the international community. Among previous commissioners is Gillian Sorensen (wife of Theodore Sorensen, the Kennedy aide, and now working as one of the few women UN assistant secretary generals as head of public affairs). Paul O'Dwyer (brother of the aforementioned Mayor O'Dwyer, whose tireless lobbying resulted in New York's snagging the UN in 1948) was Mayor David Dinkins' UN commissioner.

Annan leapt at news of the appointment of the new city cabinet member, saying in a formal statement that he was "very pleased" and looking forward to "a close and constructive relationship with the commissioner and her team in tackling many issues of mutual interest and concern." He took the opportunity also to praise Mayor Bloomberg and affirmed his belief that the UN and its host city had opened "a new chapter in their long history together." Nothing was said about the departed local hero Rudy Giuliani or his contribution to UN-New York amity. Last year Giuliani failed to show up for an important UN conference in New York on the problems of big cities. He claimed not to have received an invitation, which the organizers said had to be a nonsense excuse. Diplomats remain intrigued by the oft-told tale of Bloomberg's aspiring to head up the UN. If he's serious, it's an ambition hard to credit, since almost everyone surely knows that a national of a permanent member state of the Security Council--the US, Russia, China, France and Britain--is excluded automatically from consideration.

(However, if true, the Mayor would not be the first American to have nurtured such an idea. A biography of Franklin Delano Roosevelt mentions that when the UN was still unborn--in a way, the wartime president and Winston Churchill, the British prime minister, were its midwives--he thought of proposing himself to head the international administration. Apparently, he envisioned a smallish secretariat and considered offering his Hudson River estate at Hyde Park for it. Neither he nor Churchill--who once declared that he was not appointed the king's first minister in order to preside over the breakup of his empire--could have foreseen the anti-colonialist explosion that brought the UN from a membership of 50 states at Charter-signing to the 189 countries embraced in New York today.)

Kofi Annan, scion of an aristocratic family in what used to be the British colony of the Gold Coast before it attained independence as the republic of Ghana under the charismatic Kwame Nkrumah, is the first secretary general who can claim with considerable justification to be a New Yorker.

This undoubtedly is responsible in part for his strong personal attachment to the world's most important metropolis. Shortly after 9/11, a grieving secretary general spoke of the cruel blow suffered by "our beloved host city." Since then he has been a very visible figure at memorial ceremonies for the fallen, paid a somber condolence visit to a Midtown firehouse that lost several of its firefighters when the World Trade Center was taken out and, at least twice, has gone down to ground zero to see the devastation for himself, with Giuliani as escort.

Annan's first taste of America was as a scholarship student at Macalester College in St. Paul, Minnesota. That liberal arts institution is inordinately proud of its most famous alumnus, and justifiably so. The college took advertising space in New York to acclaim his ascent to UN chief and did so again last year when Annan shared the Nobel Prize for Peace with the organization he leads. After graduation from Macalester and before beginning post-grad work at MIT, he was employed briefly by a Midwest food grain company. After MIT, where he received a master's degree in economics, he was drawn to the international civil service; his first taste of this was as a recruit to the secretariat of the World Health Organization.

Since that lowly beginning, except for a short absence to work for the Ghana government, his entire career has been spent with the UN, most of the time in Manhattan. Before his appointment as secretary general, he and wife Nane resided on middle-class Roosevelt Island. He commuted regularly by cable car. Among the problems that the UN and New York both must grapple with are cash shortfalls. The UN is only now coming out of the red after teetering for years on the brink of bankruptcy because of the failure of many member states, notably the US, to pay their dues. The secretary general warned so regularly that insolvency was a step away that he was criticized for crying wolf. But more than once it was indeed a very close call. Financial authorities say now that the danger is past, at least for 2002. After a big infusion of lifesaving cash toward the end of last year, which restored a measure of health to the enfeebled UN treasury, the situation still is not so rosy that Annan and his accountants can get out from under the severe financial constraints that have become a familiar pattern.

Although this first secretary general from below the Sahara enjoys excellent relations, so far, with President Bush and key members of the Congress, and though Washington is no longer carping so much about the alleged "bloated bureaucracy" and its spendthrift habits, the UN remains under close scrutiny by the nations that pay the largest assessments--including the European Union states and Japan--and appeals for UN reform and maintaining strict economies in New York still have not totally subsided.

Inevitably, as in federal, state and municipal employment, UN staff are required to bear the brunt of the effects of financial savings. To that end, Annan has trimmed the secretariat staff to 8,000, its lowest number since the UN's membership expansion began in earnest.

He must make do with an annual budget that, compared with the city's, is laughable in its modest dimensions--about $1.2 billion versus $41.4 billion. But contrasting those numbers is somewhat like comparing apples and oranges. Defenders of the UN against the jibes of cost-cutters in the Congress and elsewhere receive short shrift when they cite the paltry outlays by the world body as opposed to spending for essential city services like police and fire protection. This comparison is especially inappropriate after the events of 9/11 and recurring terrorism alerts in the US.

Amazingly, given the fact that he had his own budget to prepare and present to his fiscally challenged city, Bloomberg found time in his busy schedule to pause and listen to the secretary general's woes the other day. The occasion was a private dinner hosted for the two chief executives by William Leuer, the president of the UN Association of the USA. Officials see the mayor's acceptance of the invitation as more proof, if this were needed, of Bloomberg's friendship for and, they believe, good intentions toward the UN. Joseph E. Connor, the UN's chief financial officer, was a guest at the meal. His task, in part, was to elicit mayoral sympathy for a comprehensive UN plan to expand the East River headquarters, which is both rundown and outgrown. (Just the other day, technicians were again working on cranky escalators so ancient that replacement parts must be specially replicated; the originals aren't being made any more.)

For aesthetic reasons--fear of dwarfing the elegant, adjacent General Assembly building--Annan abandoned an early proposal by the designers to add 10 floors to the secretariat office tower, the most familiar signature of the organization and an internationally recognized landmark. The original plan called for the extra floors but the $65 million loaned by the US could not cover the cost. Thus, horizontal space has to be found to expand office accommodations.

Annan and his team hope to hit up the city for a piece of real estate across 42nd Street from the headquarters. The lot now is being used for a playground. The idea, an aide to Annan says, is to relocate some staff there while other construction proceeds on the main campus in a building and refurbishing project estimated to take six years to complete at a cost of $1 billion.

The so-called master plan drawn by architects at Connor's direction includes upgrading the present buildings. Officials say the mayor is aware, as were his predecessors, that the headquarters does not comply with city construction ordinances. It likely would have been condemned long ago if it had been erected for regular commercial use, but the UN is immune from municipal rules under its extraterritoriality exemptions and an agreement concluded with the US when the decision to set up in New York was made.

Having just sought Bloomberg's sympathy for the UN's problems, the secretary general will have felt a surge of fellow feeling--been there, done that--upon hearing the mayor's presentation of his city budget on February 13. This proposes spending cuts in local government agencies, steep personnel reductions paralleling what the UN has gone through in hiring freezes and contractions by attrition, and reduced services.

One piece of bad news directly affecting the diplomatic community is a proposal to increase fines set by the city for parking violations. The city faces a huge income gap, bequeathed by Giuliani and estimated at $4.76 billion this year. Bigger fines for illegal parking are expected to help by as much as $62 million. Parking in Manhattan is a large bone of contention between the UN community and the city, and it is the first thing New Yorkers mention when they are tempted to gripe about the international guest in their neighborhood. The tabloid newspapers have long had a field day whenever the subject was aired. A classic example of the former mayor's take-no-prisoners style was his never ending war on diplomatic and consular scofflaws who abused the parking rules.

Giuliani came close to causing an international incident over it last year. Eventually, the State Department had to intervene and remind the city government that foreign affairs are best left to the folks in Washington who are paid to do that job. What the mayor possibly overlooked is that the US has diplomats abroad and they, like their counterparts in New York, are prone to traffic violations. Giuliani's plan to tow the vehicles of the most egregious culprits was overruled.

The UN committee on relations with the host country is again appealing to City Hall to have more on-street parking allocated for diplomatic and consular vehicles. It is a plea that has been addressed to virtually all of New York's mayors. As congestion worsens and more and more cars pour into Manhattan daily, despite attempts to penalize drivers with no passengers, the committee cannot be optimistic about Bloomberg's response. New York mayors have garnered few votes through pampering foreign diplomats.

Every chief magistrate of the host city has had to walk a fine line in his public attitudes toward the UN because of sensitive matters like diplomats' parking and the common perception by the electorate that there is in its midst a privileged group that does not deserve the advantages bestowed upon it. If you, why not us? In fact, the US government accorded the barest minimum of immunity to the UN in the Headquarters Agreement, compared to what diplomats and UN staff enjoy in Geneva, Vienna and other UN centers. The citizens of Bonn would love to entice the UN to move there and fill some of the office space vacated by the German government's move to Berlin. The German government has already attracted a few UN entities after offering tangible inducements. So there is competition for New York. However, Bonn is not a prospect that pleases many.

Edward I. Koch was one mayor who went through love and hate phases with the UN. At one time he tolerated the city's guest well enough to make an occasional pit stop at the delegates' bar. He cooled, however--steamed is an apter word--when the General Assembly approved a resolution declaring Zionism a form of racism. He had one descriptive noun for the offending body: "Cesspool." In New York, where there are more adherents to Judaism than in Tel Aviv, and sympathy with Israel runs high in all faiths save perhaps some Muslims, his angry reaction and choice of language touched a chord and was applauded. Koch won and, subsequently, a chastened General Assembly rethought the folly of its action, at US urging. It voted to revoke the resolution.

The conventional wisdom has it that, broadly speaking, the UN is more comfortable with Democratic administrations in Washington than with Republican ones. (Richard M. Nixon, who sent a broadcast journalist to New York as ambassador, once observed that the organization had its uses for some economic and social questions but was fit for little else.) Annan has managed to make friends in both parties, even with Jesse Helms, the former chairman of the Senate foreign relations committee, who seldom has found much to admire in the UN.

Relations between the UN and the US reached an all-time low when Boutros Boutros-Ghali of Egypt was the secretary general. Washington criticized his stewardship and vetoed his candidacy for reelection in 1996--the first UN chief to be denied a second term. (Boutros-Ghali devoted much of an autobiographical book to this blow to his pride, hotly defending his stewardship and blaming Madeline K. Albright, the US ambassador, for delivering the Judas shaft after she had professed friendship and admiration.)

Perhaps sensing the humiliation that was coming and not wishing to be replaced by a member of his own staff, Boutros-Ghali took the precaution of dispatching the popular Annan, then an undersecretary general, to a peacekeeping job in the Balkans. Of course, it didn't work.

By tradition, persons close to the secretary general never speak on the record about political personalities in member states, save perhaps for a few real villains--and, least of all, about the most important member, the US. However, there's little doubt of their preference for Bloomberg over his Democratic opponent, Mark Green. Bloomberg is a former registered Democrat who bolted the party to run for mayor as a Republican, in part, it was reported, because he felt the Democratic field was overcrowded. Al Gore was probably favored by UN folk over Bush, in part because of his environmentalist record, a subject of intense UN concern. With the benefit of hindsight, some critics now say it was an act of insanity to locate the UN in America's largest city.

It's not hard to see why, over the years, New Yorkers have been maddened more often than they were entranced by it after the initial novelty wore off. At the height of the cold war, there were all those tabloid stories of Soviet spies in the secretariat and the UN mission. When Lyndon B. Johnson was immersed in the Vietnam War, Secretary General U Thant was a constant gadfly, and an earlier White House questioned some of Secretary General Dag Hammarskjøld's policies in the strife-torn Congo.

Inhabitants of the host city have other, less sophisticated gripes, like the inconveniences they endured when Annan hosted the Millennium Summit in September 2000, attended by more than 140 heads of state or government. This was a classic example of the turmoil that can surround the UN presence, and only five years after Boutros-Ghali had pulled the same trick with the UN's 50th anniversary bash.

In a small token of contrition toward a sorely tried populace, Annan's message, "Thank you NYC," was spelled out in lights on the headquarters frontage after the millennial event concluded. Extreme security restrictions were put in place after Sept. 11 and, most recently, during the World Economic Forum's meeting in Manhattan, when UN headquarters was expected to be a potential target for protesters. Annan supports globalization, which those protesters oppose, and made the case for it in his address at the Forum on its final day.

In delivering his inaugural address, Mayor Bloomberg may have missed an opportunity to repeat the Capital-of-the-World claim that Giuliani enjoyed, or even to mention the presence of the UN, but he did say that "New York is the best place in the world to do business" and that "no city can match New York for its intellectual capital, financial know-how and cultural vibrancy." Most people at the UN will hardly dispute that assessment.

In a way, New York is a mostly harmonious microcosm of the UN, or, more precisely, of what the UN could be. "This is a city," said Bloomberg, "where 140 languages are spoken. Since the days of the Dutch, wave after wave of immigrants have transformed this city. They have flourished because of the culture of tolerance and acceptance that characterizes New York. Our challenge is to strengthen the culture and fight bigotry in any form, wherever it may happen."

Bloomberg, the Democrat turned Republican, went on: "Those of us in government must remember that we are here to work with and serve eight million New Yorkers Š In the next four years I will devote myself to building a better New York. I promise that I will listen and, whether you ultimately agree with my decisions, you will know that your voice has been heard." It could have been a UN speechwriter's prose.