Now, the 50-year-old is facing a severe midlife crisis, waging war for the first time in its history. So whom does NATO turn to in its time of need? Its historic adversary, Russia, with no seat at the party.
Two questions arise: Does Russia have enough influence with Yugoslav President Slobodan Milosevic to deliver a deal that would end the fighting? And, more significant, absent a role for Russia, is its relationship with NATO fatally wounded?
On the eve of the summit, Russian mediator Viktor S. Chernomyrdin emerged from nine hours of talks in Belgrade to say Milosevic was willing to accept the presence of an international military force in Kosovo. Chernomyrdin said that there was no agreement on the makeup of such forces but that ``the main thing is that Russia will take part in them.''
It is a step forward but not a breakthrough. NATO replied Friday that the concession had fallen well short of what it had wanted.
Lost in the back and forth, meanwhile, was the change in Chernomyrdin's tune. The former prime minister has stopped singing with the Kremlin choir condemning the bombing campaign and has called for an end, as well, ``to ethnic cleansing and separatism'' in Kosovo.
Is there the shape of a deal here? Russia would triumph grandly if it was to prove indispensable to a solution while safeguarding Milosevic's interests. More likely, Russia would work quietly with the weaker NATO members to force a settlement so that good relations between the great powers could be restored.
And Russia may alter its posture, depending on whether NATO looks united or shaky after the summit.
But there is huge doubt, even among Russians themselves, that Russia can deliver.
``I don't think it's a very credible role [as mediator], because Moscow has little leverage with Milosevic,'' said Dmitri Trenin, a Russian military expert and deputy director of the Moscow Carnegie Center. ``It can only act as a messenger. The appointment of Chernomyrdin was to salvage something of the relationship with the United States.''
The assumption that Russians take the side of the Serbs because they are Slavic brothers is only partly correct. In fact, Yugoslavia was considered more on the side of NATO during the Cold War than on the side of the Soviet-led Warsaw Pact. There also is no strong religious connection that binds the peoples.
``I think Milosevic despises the Russians more than some other peoples,'' Trenin said.
Alexander M. Haig Jr., the former secretary of state and NATO commander, wrote in Friday's Wall Street Journal that Russia has never delivered an agreement from the Serbs ``despite its supposed influence'' with Milosevic.
``Is this the `partner' who will mediate a solution to Kosovo?'' Haig asked.
He may be right, but there are reasons for Moscow's reluctance to take up NATO's cause wholeheartedly. As the saying goes, just because you're paranoid doesn't mean someone isn't after you.
The Russia that the West is dealing with now is a country suffering from post-empire blues, an inferiority complex exacerbated by an economic collapse, the rape of its natural resources by quick-hit investors, and repeated humiliation by the International Monetary Fund.
In short, it's the poor man of Europe.
Instead of including Russia as an equal partner in a comprehensive European security system, NATO has expanded eastward and waved the red flag of membership for Baltic and Balkan nations in Moscow's face, thus fueling the anti-West rantings of Russian nationalists and making the democrats look gullible.
Even ardent pro-Westerner Grigory Yavlinsky has called NATO's recent inclusion of the Czech Republic, Hungary and Poland ``evidence that the West does not believe in Russia's becoming a democracy in the near future.''
Before Kosovo, Russia worried that NATO's new doctrine of ``out of area'' strategic operations was at odds with its stated profile as a defensive alliance. That worry has taken on a concrete shape, now that cruise missiles are hitting Belgrade.
Russian analysts say the NATO-Russia relationship has been severely, perhaps permanently, damaged. The anti-American media campaign has subsided, though lasting damage has been done.
Alexei Arbatov, deputy chairman of the defense committee in the Russian Duma, said this was the most dangerous crisis in U.S.-Russian relations since the Cuban missile crisis in 1962.
``Some political elites in Moscow see NATO as the main threat to Russia,'' Trenin said.
The view is shared in Russia by communists and liberals. According to analysts, the Russians feel deceived by the way the European security architecture has been designed.
``The Russians know they cannot dominate Europe - they can't even dominate Chechnya - but they wanted an equal footing in the Organization on Security and Cooperation in Europe,'' Trenin said. ``Now, NATO is the only dominant security alliance.''
Russia's role in the NATO-Russia Permanent Joint Council, established two years ago, has been a failure. The Russians say they were allowed joint consultation on security issues, instead of joint decision-making and joint action. The council seems to have been the sugar coating on the bitter pill of NATO expansion that Russia was forced to swallow.
Within Russia, the NATO action in Kosovo has weakened democrats, who advocate more interaction with the West. Likely presidential candidates Yuri Luzhkov, the mayor of Moscow, and retired Gen. Alexander Lebed will accentuate their nationalistic positions in an effort to appeal to an angry electorate.
The prime beneficiaries of NATO's actions are the communists and the followers of ultranationalist Vladimir Zhirinovsky.
Many Western veterans of the Cold War and champions of the alliance believe nothing can be done to ease Russia's paranoia.
Peter Rodman, who served in the Reagan administration as a national security adviser, said any delay in additional NATO expansion of the alliance would be ``gratuitous, pointless and possibly dangerous.''
Said Haig: ``The alliance will never make the Russians happy unless it becomes a mere debating society.''
Yet as the alliance closes its commemoration today, it may consider that a Russia that was once its reason for existence may be vital to its continued credibility.
If a political solution can be found before the war engulfs Macedonia and more of the region and Russia is seen to have played a role in the settlement, then some of the damage can be undone.
``My concern is that NATO's blunders could be matched by Russia's blunders,'' Trenin said. ``If there is a wider war, it will be hard for Russia to stay on the sidelines.''