Opinion | Give Ukraine NATO Membership. Peace Depends on It.

In Washington and New York last month, President Volodymyr Zelensky of Ukraine said his country’s people were fiercely committed to a just and lasting peace to end the war on their nation. This week in Kyiv, I heard a similar sentiment from every Ukrainian I spoke with, from senior officials to frontline soldiers. They want Russians out of their country and security guarantees to protect Ukrainian sovereignty.

When the war ends, Ukraine must join NATO. An end to the conflict will come either with Ukraine repelling the Russian invaders or with the international community pressuring Russia to halt it, or both, as President Zelensky has suggested. But without Ukraine in the alliance, that nation will never be safe from the Russian aggression that has menaced it for 300 years, and Europe as a whole will not be secure.

President Vladimir Putin of Russia has made clear he intends to eliminate Ukraine as a nation. He took a step in that direction in 2014 when he invaded Ukraine and occupied Crimea, and since February 2022 he has attempted to smash Ukrainians into submission through his savage invasion.

With support from the United States, Canada and Europe, and allies and partners in the Indo-Pacific, Ukraine has held off the Russians for two years and eight months. Ukrainians have shown that they will continue the fight and, as President Biden has said, will win. But they have been clear they need more support during the war and NATO membership after.

The last time the United States tried to secure NATO membership for Ukraine, at the NATO summit in Bucharest, Romania, in 2008, we failed. Some policy experts in Washington use that as an excuse to say the NATO alliance will never accept Ukraine a member. I was the U.S. ambassador in Kyiv at the time, and I think the real lesson is different: We might have succeeded if we had started earlier and pushed harder.

A decision to invite Ukraine (and Georgia) to begin the process of joining NATO was high on the agenda in Bucharest. President George W. Bush had pushed his administration and the other NATO leaders to move ahead with that decision. Unfortunately, he started too late.

At a meeting in Washington of U.S. ambassadors to European capitals in late 2007, I recall asking then-Secretary of State Condoleezza Rice if we would be supporting a membership plan for Ukraine at the Bucharest summit. The secretary, somewhat uncomfortably, indicated that we would not. Some NATO allies, including, critically, Germany, soon got the message and decided to oppose the action, primarily because they understood it to be the U.S. position.

U.S. opposition to NATO membership for the two countries lasted until President Bush sat down with his secretaries of state and defense and Vice President Dick Cheney at a regular Wednesday policy session in late February 2008, less than two months before the Bucharest summit was to start.

President Bush decided that the United States would support NATO membership for Ukraine after all. He directed his national security adviser, Steve Hadley, to seek German agreement. Mr. Hadley tried, but Berlin would not agree. President Bush decided to push on.

In taking that stance, he echoed an important powerful theme of post-Cold War U.S. policy: Formerly captive nations should be free to choose their own destiny.

To build momentum for Ukrainian membership, President Bush visited Kyiv on his way to the summit. He was impressed by the Ukrainians’ resolve and flew on to Bucharest determined to argue for membership. The Germans — and the French — however, were immovable in their opposition. Both countries believed they could shape Russian actions by forging closer ties with Moscow — mistakenly, as it turned out. Former Chancellor Angela Merkel of Germany later acknowledged that concerns about potential negative reactions from Russia shaped German decision-making.

President Bush and Secretary Rice were able to get a statement in the final communiqué affirming that Ukraine would eventually be in NATO, but without any indication of when or how. (This was also the meeting where Mr. Putin, a guest, leaned over to President Bush and famously said Ukraine is “not a real country.”)

NATO’s failure to offer Ukraine and Georgia a course toward membership most likely led Mr. Putin to conclude that the West would not support those two countries if he attacked them. He invaded Georgia four months later and Ukraine for the first time six years after that. Had NATO started Ukraine and Georgia on the path to NATO membership in 2008, Russia might not have invaded the two nations and Ukraine might not be enduring today’s terrible Russian war.

So, what are the lessons from 2008 for today? First, one can deduce that NATO membership is necessary to deter Russian aggression. Mr. Putin so far has attacked only non-NATO countries. Second, to achieve NATO membership for Ukraine, the United States must start early, making it a clear priority for the next NATO summit, in June. It must use all the leverage it has in a sustained campaign to persuade NATO allies to take this step.

Many allies now support NATO membership for Ukraine, including France, Britain, Poland, the Baltic States, the Nordic nations and most of Central and Eastern Europe. Several more indicate that they will not stand in the way. Again, Germany will be key. Then Hungary, Slovakia and Turkey will have to be convinced. With sufficient commitment and determination, it can happen.

NATO allies agree that Ukraine has more work to do on reform before it can be admitted to the alliance. Ukrainians are committed to these steps and have made great progress since President Biden’s visits as vice president 10 years ago. Ukraine is making significant progress toward membership in the European Union, including the political and economic reform that process requires.

Russia may not be happy with Ukrainian NATO membership. But this is not about pleasing Russia. This is about lasting peace and security. Moscow does not get a veto.

Meanwhile, NATO should take interim steps to begin incorporating Ukraine into the alliance. The Ukrainian ambassador to NATO should be made an ex officio member of the North Atlantic Council, the alliance’s main decision-making body, with a guaranteed seat at the table for every meeting. A senior Ukrainian officer should be invited to participate in meetings of the NATO Military Committee. Ukraine should be invited to contribute troops to the Joint Expeditionary Force, a British-led multinational formation whose members are all NATO allies. Most important, the alliance should invite Ukraine to begin membership negotiations immediately, so that when the conflict ends, Ukraine will be instantly ready to formally join.

Europe will not be secure — and will not be whole and free — until Ukraine is in NATO. Ukraine will not agree to end the war without it. The United States is key and must show sustained, persistent and creative leadership. With confidence and strength, and a lot of hard work on all sides, Ukraine can become a member of NATO. For peace in Europe, it must.

William Taylor was the U.S. ambassador to Ukraine from 2006 to 2009 and chargé d’affaires there from 2019 to 2020.

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