Few today remember the exhilaration with which people across the globe, including Americans, greeted the signing of the San Francisco Charter and the founding of the United Nations in 1945. There had been two massive military convulsions in just a quarter-century; many millions were dead; a whole continent was in ruins. And so there was a pervasive sense that, after the failure of the League of Nations, a new world order was required to prevent another catastrophic conflict. The UN Charter, which was designed not only to “save succeeding generations from the scourge of war” but also to reaffirm fundamental human rights, added to the heady sense that after all the horrors, a new and better world was finally in view.

Sixty-some years on, most of that exhilaration is gone: multilateralism is disdained in this age of American hegemony, and the UN is held in low esteem by many in the United States. Even so, the UN has survived and flourished, expanding its functions far beyond what its founders envisioned. However imperfect, the UN is the only place where governments of all nations can gather to deliberate, raise common budgets, and organize international initiatives. The Security Council can be summoned day or night, and it’s as effective as its key members permit it to be. The Secretariat, for all its problems, is available to coordinate security and peacekeeping operations and to deal with the needs of member states. The vast panoply of UN organizations includes the International Court of Justice, whose purpose is to affirm the rule of law; critically important financial institutions like the International Monetary Fund; an international human-rights regime; the world’s refugee agency; as well as social, agricultural, economic, and health agencies. The secretary general has become one of the world’s preeminent political figures, his office commanding an ideal platform from which to draw international attention to the plight of those threatened by war, oppression, and poverty. All this is part of the long and complicated story brilliantly told by Paul Kennedy in The Parliament of Man.

The UN’s first great success was its ability to bring all the major powers together-and keep them together. The League of Nations had failed because the United States and other powerful countries were absent or immobilized in the face of major crises such as Mussolini’s invasion of Ethiopia. The UN resisted demands for strict equality among member states and put the five victors of World War II in control as veto-wielding permanent members of the Security Council. The drafters of the UN Charter thus made sure that collective-security efforts could not be derailed by small renegade states. The disadvantage of this arrangement was that it aggravated divisions between poor countries (mainly in the global South) and rich ones (mainly in the North)-divisions that persist to this day.

The new system responded well to its first major test in 1951, when China invaded North Korea. Its efficiency on this occasion was partly the result of the Soviet Union’s decision to walk out over another issue. But the Security Council froze up during much of the cold war, with the Soviet Union and the United States both exercising their veto power dozens of times. (The Soviets often used their veto to block unwanted new members, while the Americans used theirs in response to emerging North-South issues, the Israeli-Palestinian conflict, and civil wars in Africa.) It was only after the collapse of the Soviet Union-when Russia and the United States were finally willing to cooperate on a wide range of regional problems-that the UN was put to fuller use. In the 1990s, the Security Council approved several complex operations and peacekeeping missions, though often without the resources those missions required.

Still, there were notable successes, such as the Security Council resolutions ending the Iran-Iraq war in 1988 and the Soviet withdrawal from Afghanistan, which was facilitated by the secretary general. The Security Council condemned Iraq’s invasion of Kuwait the day after it happened in 1990. But the UN’s reluctance to intervene in the Bosnian blood bath undermined its credibility, as did its slow response to several subsequent crises in failed or failing states. Then too, the secretary general had to cajole members for contributions of peacekeepers, funds, and supplies. By 1993, the cost of the UN’s peacekeeping force was more than twice its regular budget, and this produced massive “donor fatigue,” notably in Washington.

The UN’s most recent failures-the ghastly genocide in Rwanda, the slaughter at Srebrenica, the recriminations among members of the Security Council over their inability to agree on a second Iraq resolution, the oil-for-food scandal, and now Darfur-have done serious damage to the institution’s reputation. These episodes are revisited in The Best Intentions, James Traub’s account of Kofi Annan’s turbulent period as secretary general. This book is arguably the best contemporary case study of the UN’s inner workings. Kofi Annan emerges from Traub’s chronicle as a man of immense decency and dedication, but also as someone vulnerable to the successive right-wing attacks of Jesse Helms and John Bolton. Better than anyone else, Annan understood that the will to reform the UN must come from its leading member states, states that often helped to create the very situations they deplored-and for which they too often blamed the UN and the secretary general in particular.

The need for some kind of reform is obvious. It has been clear for years that the makeup of the Security Council no longer reflects the actual distribution of geopolitical power. Countries with growing demographic, political, or economic clout, such as India and Brazil, clamor for greater recognition and influence. In fact, the entire UN system for formulating and enforcing resolutions needs updating. In order to be an effective guarantor of human rights, the UN should have standing peace-keeping forces in various continents. And, more generally, the UN should have a staff commensurate to its growing tasks. Because any serious effort to reform the institution will have to overcome huge political obstacles, Paul Kennedy argues for a moderate, incremental approach. For now at least, a total overhaul seems too much to demand, but an imperfect UN is better than nothing.

With or without reform, the grave challenges that face the world will likely force the UN into greater prominence. The looming catastrophe of global warming, ongoing nuclear proliferation, global poverty, and the threat of pandemic-these are urgent issues that cannot be dealt with unilaterally. They all require international cooperation, of a kind that depends on American support. These thought-provoking books should therefore be required reading for members of Congress, diplomats, soldiers, university students, and all those in the Senator Helms tradition of contempt for this flawed but indispensable “parliament of man.”