NATO’s future is intimately connected to both its past and present. It has, after all, survived half a century of extraordinary change in very good order. It spectacularly proved its enduring relevance on September 12, 2001, when Article 5, the collective defense clause designed to save Europe from the Soviet Union, was invoked to help the United States from the new and evil scourge of mass terror.

As the organization’s tenth Secretary General, in 2002 I saw the final divisions and stereotypes of the Cold War smashed around the NATO-Russia Council table at its first meeting in Rome and NATO’s largest ever enlargement in Prague. In the rubble of the World Trade Center, I saw what the terrorists could do as well as how NATO could regroup to help defeat them. I saw NATO troops bringing hope to the streets of Kabul, a continent and a half away from the old Iron Curtain. Most of all, I saw a transformed Atlantic Alliance doing what it has done best since 1949: delivering safety and security where it matters and when it matters.

In 1949, the Washington Treaty, on which the Atlantic Alliance is based, was written. The authors wanted the language to be as clear and concise as possible. Most writers claim this as the goal, but few deliver. However, one of the authors had a benchmark: that the Treaty should be written so that it could be understood by a milkman from Omaha. That Nebraskan dairyman turned out to be an excellent editor, because the Washington Treaty is a model of clarity and brevity.

How would the Alliance’s first editorial influence react to the new NATO, 55 years on? What would he understand? Or, indeed, completely fail to comprehend? First of all, our milkman would be surprised to find that the Alliance is still in business. Based on his own experience, he would have expected the Yanks to come home and the Europeans to fall out, but neither happened. More recently, historians told us that alliances between free nations do not survive the disappearance of the threat that first brought them together.

NATO has disproved that argument. The Warsaw Pact disintegrated and NATO modernized. The first reason was to help spread security and stability eastwards across Europe. Then NATO went on to use its unique multinational military capabilities to bring peace to Europe’s bloody and chaotic Balkan backyard. Bosnia, Kosovo and Macedonia are no longer in the headlines because NATO acted, learned lessons, and put them into practice. NATO helped stop civil war in Bosnia, acted to prevent ethnic cleansing in Kosovo, and intervened to prevent a civil war in Macedonia. In each successive crisis, NATO’s involvement came at an earlier stage and was therefore increasingly effective in saving lives and preventing overspill. The Alliance was prepared to stay the course. Today, the new threats of terrorism in our post-September 11 world must be confronted.

The challenges have changed, but so too has NATO. Our milkman would understand and approve. He would do the math: 12 members in 1949 and 26 today, a clear message of success. He might, however, wonder what had happened to the old adversary, the Soviet Union.

Here, however, his perspective would be different from ours. From his 1949 vantage point, only four years after the end of the common struggle against fascism and with the Iron Curtain only beginning to fall across Europe, he might not be that surprised to hear that we are once again partners with Russia. But for the children of the Cold War, the journey from the shadow of mutual extinction to a NATO-Russia Council in which Russia sits as an equal with 26 NATO members to deal with the common threats of the 21st century is nothing less than epic. We might still have our differences with Russia, but they are the signs of politics and diplomacy, not of mutually assured destruction.

No matter how capable NATO is, it cannot meet today’s challenges on its own. Reliable friends are needed, as are partners—hence the engagements with the Euro-Atlantic Partnership Council (EACP) and Partnership for Peace countries in the fight against terrorism. These arrangements offer groups opportunities for more individualized cooperation with NATO, and stimulate them to cooperate with their neighbors to tackle regional problems. Together, the 46 countries in the EACP form the world’s largest permanent coalition. In parallel, NATO has built truly groundbreaking partnerships with Ukraine and especially with Russia.

The decision to admit seven new members from the Baltic to the Black Sea was highly symbolic, but it was also eminently practical. All of the new Allies add value to collective security. NATO’s first multinational chemical, biological, radiological, and nuclear defense battalion was seen as a key capability in today’s military armory. This new battalion was to be launched and led, not by the traditional NATO heavyweights, but by the Czech Republic, one of the first wave of new members. It was admitted only five years ago, but are now self-confident and capable enough to lead one of NATO’s most important projects.

Our Omaha milkman would, I am certain, understand and approve. But he might still have one or two difficult questions to ask. How, for example, will an Alliance created for the Fulda Gap fare beyond the Hindu Kush? The answer is that NATO will succeed because it has no other option.

If we want to win the fight against terrorism, we have to succeed in Afghanistan. Failure would not just be a disaster for the Afghan people and a blow to the international fight against terrorism. It would also undermine NATO’s credibility. NATO has not failed in its 55-year history, so there is every reason to believe that it will succeed in Afghanistan as well. But it will not be easy.

NATO’s Problems

The changes in NATO’s role were not agreed upon overnight, but the remarkable fact was that they were agreed upon at all. When the international community and practically every other multilateral institution were split over Iraq, NATO was able both to agree and to act. It took 11 difficult days in February 2003 to meet Washington Treaty commitments and reinforce Turkey, but NATO did so when others failed. Moreover, in building agreement, it confounded the critics who said that this crisis would permanently shatter NATO’s cohesion. Only weeks later, the Alliance unanimously took two previously unthinkable decisions. First, to take over the International Security Assistance Force in Kabul; then, to provide support to Poland and Spain in setting up their stabilization division in Iraq.