President Zelensky may not like it, but the answer to the crying need for Ukraine’s defenses, both permanent and short-range, has a unique precedent in the guarantees for defense of another beleaguered nation caught in the nexus of conflicting forces.

That precedent would be Israel, the recipient of more than $3.5 billion annually in American military aid — more than any other country except for Ukraine. Pleas for what is sometimes called an “Israel-style” form of security that ensures no external power can penetrate its defenses are spreading among leaders of the 31 NATO nations now meeting at the Lithuanian capital of Vilnius, where defense of Ukraine is the all-consuming topic.

Led by President Biden, the NATO members are recognizing that there’s no way they can come to terms with admitting Ukraine in the midst of war. One problem is that if Ukraine were a full alliance partner, NATO nations would have to pour their own troops into that country rather than go on waging what has devolved into a semi-permanent form of war by proxy.

The benefit of an Israel-style defense of Ukraine is that Ukraine, like Israel, would never be a member of a formal alliance even though it would have, in theory at least, one of the most stable, invasion-proof defensive walls against attacks by air, on the ground, and at sea. 

Moreover, armed with billions of dollars of increases in aid on almost a permanent basis, Ukraine could exist without the unending fear of Russian invasion — a semi-permanent form of terror going back to tsarist times. Russian domination reached its hideous worst when the former Soviet Union was ruled by the dictator blamed for the deaths of 20 million Ukraine citizens in the 1930s, Josef Stalin.

The prospect of a solid guarantee of defense may provide relief for Mr. Zelensky but is far from what he wants — if not immediate entry into NATO, then the assurance that Ukraine will be admitted into the club in the near foreseeable future.

Mr. Zelensky signaled his unhappiness in an outspoken tweet as he was on his way to Vilnius and a round of speech-making and lobbying in which he will plead his case not only for unremitting aid but also for recognition by NATO members as a full-fledged power eligible for acceptance like most other European nations.

“We value our allies,” he tweeted. “We value our shared security.” Nonetheless, he stated, “on the way to Vilnius we received signals that certain wording is being discussed without Ukraine.” It was, he said, “unprecedented and absurd when time frame is not set neither for the invitation nor for Ukraine’s membership.”

His rage increased as he was writing the message. “While at the same time vague wording about ‘conditions’ is added,” he ranted, “it seems there is no readiness neither [sic] to invite Ukraine to NATO nor to make it a member of the Alliance.”

Mr. Zelensky perceived the possibility of betrayal in peace talks that would compromise away portions of Ukraine that have long since fallen into Russian hands.

“This means that a window of opportunity is being left to bargain Ukraine’s membership in NATO in negotiations with Russia,” he said. “And for Russia, this means motivation to continue in terror. Uncertainty is weakness. And I will openly discuss this at the summit.”

Mr. Zelensky’s concerns were sure to inspire controversy among NATO’s many members considering that at least two of them, Hungary and Turkey, have strong Russian ties. The decisions of Prime Minister Orban and President Erdogan to go along with the admittance of Sweden to NATO may have headed off immediate disagreement but won’t stop them from encouraging talks — and possible compromise — with Russia.

The idea of defending Ukraine in the style of defense of Israel is also not without controversy.

“The ‘Israel model’ has quickly gained traction in Washington and among NATO allies eager to enhance Ukraine’s future security,” a study titled “The Promise and Pitfalls of an ‘Israel Model’ for Ukraine,” published this month by the Stimson Center at Washington, says.

The study observes that “a highly credible security commitment” to Kyiv could pose “risks” for Washington in the event that “the relationship becomes untethered from US national interests.”

Israel-like security guarantees might get around the thorny question of admitting Ukraine to NATO, the study says, but they pose the danger of emboldening risky or provocative behavior by Ukraine if its leaders “come to believe that Washington will always be there to bail them out.”

Mr. Biden, sweet-talking with Mr. Zelensky, smiling his way through meetings with NATO leaders, was certain to fend off moves for full NATO membership while coming up with a compromise that the Americans think will work.

Ukraine’s prime minister, Denys Shmyhal, was pragmatic. NATO and Ukraine need each other, he observed: “The practical support provided by NATO and the member states of the Alliance … help liberate our territories.”

In the end, for Ukraine, the choice may come down to take it or leave it. NATO membership surely was “one of Ukraine’s geopolitical priorities,” Mr. Shmyhal said, while the immediate priority remains where it’s always been, defeating the invaders.