When I first became president, I said that I would support Russian President Boris Yeltsin in his efforts to build a good economy and a functioning democracy after the dissolution of the Soviet Union—but I would also support an expansion of NATO to include former Warsaw Pact members and post-Soviet states. My policy was to work for the best while preparing for the worst. I was worried not about a Russian return to communism, but about a return to ultranationalism, replacing democracy and cooperation with aspirations to empire, like Peter the Great and Catherine the Great. I didn’t believe Yeltsin would do that, but who knew what would come after him?

If Russia stayed on a path toward democracy and cooperation, we would all be together in meeting the security challenges of our time: terrorism; ethnic, religious, and other tribal conflicts; and the proliferation of nuclear, chemical, and biological weapons. If Russia chose to revert to ultranationalist imperialism, an enlarged NATO and a growing European Union would bolster the continent’s security. Near the end of my second term, in 1999, Poland, Hungary, and the Czech Republic joined NATO despite Russian opposition. The alliance gained 11 more members under subsequent administrations, again over Russian objections.

Lately, NATO expansion has been criticized in some quarters for provoking Russia and even laying the groundwork for Vladimir Putin’s invasion of Ukraine. The expansion certainly was a consequential decision, one that I continue to believe was correct.

As United Nations ambassador and later secretary of state, my friend Madeleine Albright, who recently passed away, was an outspoken supporter of NATO expansion. So were Secretary of State Warren Christopher; National Security Adviser Tony Lake; his successor, Sandy Berger; and two others with firsthand experience in the area: Chairman of the Joint Chiefs of Staff John Shalikashvili, who was born in Poland to Georgian parents and came to the U.S. as a teenager, and Deputy Secretary of State Strobe Talbott, who translated and edited Nikita Khrushchev’s memoirs while we were housemates at Oxford in 1969 and 1970.

At the time I proposed NATO expansion, however, there was a lot of respected opinion on the other side. The legendary diplomat George Kennan, famous for advocating for the policy of containment during the Cold War, argued that with the fall of the Berlin Wall and the dissolution of the Warsaw Pact, NATO had outlived its usefulness. The New York Times columnist Tom Friedman said Russia would feel humiliated and cornered by an enlarged NATO, and when it recovered from the economic weakness of the last years of Communist rule, we would see a terrible reaction. Mike Mandelbaum, a respected authority on Russia, thought it was a mistake too, arguing that it wouldn’t promote democracy or capitalism.

I understood that renewed conflict was a possibility. But in my view, whether it happened depended less on NATO and more on whether Russia remained a democracy and how it defined its greatness in the 21st century. Would it build a modern economy based on its human talent in science, technology, and the arts, or seek to re-create a version of its 18th-century empire fueled by natural resources and characterized by a strong authoritarian government with a powerful military?

I did everything I could to help Russia make the right choice and become a great 21st-century democracy. My first trip outside the United States as president was to Vancouver to meet with Yeltsin and guarantee $1.6 billion for Russia so it could afford to bring its soldiers home from the Baltic states and provide for their housing. In 1994, Russia became the first country to join the Partnership for Peace, a program for practical bilateral cooperation, including joint training exercises between NATO and non-NATO European countries. That same year, the U.S. signed the Budapest Memorandum, along with Russia and the United Kingdom, which guaranteed Ukraine’s sovereignty and territorial integrity in return for Ukraine’s agreement to give up what was then the third-largest nuclear arsenal in the world. Beginning in 1995, after the Dayton Accords ended the Bosnian War, we made an agreement to add Russian troops to the peacekeeping forces that NATO had on the ground in Bosnia. In 1997, we supported the NATO-Russia Founding Act, which gave Russia a voice but not a veto in NATO affairs, and supported Russia’s entry to the G7, making it the G8. In 1999, at the end of the Kosovo conflict, Secretary of Defense Bill Cohen reached an agreement with the Russian defense minister under which Russian troops could join UN-sanctioned NATO peacekeeping forces. Throughout it all, we left the door open for Russia’s eventual membership in NATO, something I made clear to Yeltsin and later confirmed to his successor, Vladimir Putin.