Ukraine Is Knock, Knock, Knocking on NATO’s Door

TALLINN, Estonia—One question dominates debates between American and European leaders, and it’s one that Ukraine views as existential. It is also, for now, unanswerable: When will Ukraine join NATO?

TALLINN, Estonia—One question dominates debates between American and European leaders, and it’s one that Ukraine views as existential. It is also, for now, unanswerable: When will Ukraine join NATO?

Even before Russia launched its full-scale invasion of Ukraine last year, Kyiv was pushing Washington and other European powers for a clear path to NATO membership, viewing the powerful alliance as central to its shift out of Russia’s orbit and into the Western fold. It was an ambition that likely helped push Russian President Vladimir Putin, who views NATO as a strategic rival, to launch the invasion, bringing to Europe the largest conflict since World War II.

The debate over how and when NATO should admit Ukraine into its alliance has taken on an increasingly urgent tone here in Eastern Europe among countries whose officials say several major NATO powers, including the United States and Germany, are pumping the brakes on setting a concrete timeline for Ukraine’s membership in the short term. That debate has caused tensions behind the scenes within the alliance, even as its members put on a united front in public and continue shipping military supplies to Ukraine ahead of an expected spring counteroffensive against Russia. (Some analysts believe that counteroffensive has already begun.)

Officially, all 31 leaders in NATO have publicly agreed to bring Ukraine into the alliance, according to NATO Secretary-General Jens Stoltenberg—even if all agree that full membership isn’t realistic as the war continues. But Ukraine and its strongest supporters, particularly Eastern European countries already in NATO and closer to Russia’s borders, are saying that pledge in itself isn’t good enough. A key test of how this debate plays out will come in July, when NATO leaders meet for a major summit in Vilnius, Lithuania.

At a meeting of NATO foreign ministers last month, the Biden administration sided with Germany and Hungary to resist proposals from Poland and the Baltic states to emerge from the Vilnius summit with a concrete road map and possible timetable for Ukraine to join NATO, according to four Western and NATO officials familiar with the matter. That pushback has incensed NATO’s Eastern European allies, who are intent on lobbying Washington to change its course ahead of the summit, these officials said. All officials spoke on condition of anonymity.

Other current and former NATO officials who spoke to Foreign Policy have also quietly cast doubt on how long it would take Ukraine to be admitted to NATO, even if the war ends in Ukraine’s favor and NATO leaders give the greenlight to formally start the process. Admitting a new member requires unanimous approval from the legislative bodies of all NATO members, a difficult political feat to take on across 31 countries, as seen by Sweden’s rocky and monthslong efforts to join NATO this year. Finland hoped to join NATO simultaneously with neighboring Sweden, but that plan fell apart due to pushback from Turkey. Finland joined NATO alone last month; Sweden is still waiting.

“We know how cold it is sitting on the outside waiting to get in,” said Nikola Dimitrov, a former foreign minister to North Macedonia who oversaw the final stages of his country’s yearslong accession to NATO in 2020. 

Ukraine sees eventual NATO membership as essential to its survival, and Ukrainian President Volodymyr Zelensky has launched a fresh diplomatic campaign in European capitals to lobby for support, visiting Italy, Germany, and France this week. Many officials in Eastern Europe say that even if this current war goes Kyiv’s way, Russia won’t stop trying to forcibly drag Ukraine back into its orbit unless and until it joins NATO and can shelter under the alliance’s collective defense and nuclear umbrella. 

“We have to send the message publicly that the process is starting,” said Estonian Foreign Minister Margus Tsahkna on the sidelines of the Lennart Meri Conference, a major annual European security forum in Tallinn. “To stay in the waiting room of NATO is the most dangerous place of all.” 

But NATO’s collective defense clause, seen as the bedrock of deterrence against Russian invasion, could risk dragging the entire alliance into a war with Moscow if Ukraine’s membership is poorly timed—a grim prospect given the nuclear weapons each side has aimed at the other. Article 5 of NATO’s founding treaty says an attack on one ally is an attack on all allies and is viewed as the basis of the alliance’s deterrence against Russia. 

The debate over when to admit Ukraine to NATO strikes at the heart of the West’s vision for a post-Cold War order. The vision of a Europe whole and free and at peace, as former U.S. President George H.W. Bush put it, was sorely tried when Russia launched its invasion last February. The war has killed or wounded more than 354,000 soldiers on both sides so far, according to a cache of U.S. intelligence documents leaked online and discovered last month. 

Enlarging NATO and the European Union over the past three decades to embrace former Soviet-bloc states became a central pillar of U.S. and European policy. In the past, enlargement debates centered on the soft-power allure of Western institutions and whether a country had undergone enough governance and market reforms to be worthy of joining. Now, leaders are faced with the prospect of expanding their borders to a country in the midst of war, and the conversation over enlargement has taken on a more hard-power, geopolitical tenor. “Peace and stability in Europe relies on a strong and stable Ukraine as a bulwark against an aggressive Russia,” former NATO Secretary-General Anders Fogh Rasmussen said at the Copenhagen Democracy Summit on Monday.

Officials in Eastern Europe often refer to countries outside NATO or the EU—including Ukraine, Moldova, Georgia, and some countries in the Balkans—as in a “gray zone.” They view these countries as particularly vulnerable to Russian pressure, from disinformation and political meddling to—in the case of Ukraine as well as Georgia in 2008—military invasion. 

“A gray zone is a greenlight” for Russia to interfere in these countries, said Kurt Volker, a former U.S. ambassador to NATO. 

This isn’t the first time that the alliance said it would open the door to Ukraine. At a summit in Bucharest in 2008, NATO declared that Ukraine and Georgia would one day join the alliance, led by efforts from then-U.S. President George W. Bush. But that declaration never made it beyond the piece of paper it was written on, due to French and German opposition to both countries starting the formal road map to joining the alliance, called the Membership Action Plan.

Officials in the region saw that saga as a strategic disaster, giving Putin the idea that he had time to stop NATO expansion after Western powers declared their plans but while they were still waffling. Within four months of that summit, Russia launched a military invasion of Georgia. To this day, Russia controls some territories of Georgia, and Georgia’s path to NATO membership has been put in permanent limbo. 

“The Vilnius summit shouldn’t repeat the mistakes which have been made in Bucharest,” Daria Zarivna, an advisor to Zelensky, said at the Copenhagen Democracy Summit.

“We can’t just regurgitate the same language from Bucharest, and there’s no way Ukraine would accept that,” said a senior official from an Eastern European country involved in the alliance debates on the matter. “There would be no bigger gift for Putin than that.”