During his recent visit to Washington, NATO Secretary General Jens Stoltenberg faced the unenviable task of easing concerns about whether the United States would pull out of NATO while pushing back against President Trump’s impulse to do so. Trump has never hidden his disdain for NATO — or alliances more broadly. Recent reports of his private threats to withdraw, amplified by Jim Mattis’s resignation as defense secretary while stressing disagreement with the president about NATO’s importance, have raised the real possibility Trump may actually pull the Twitter trigger.

Although such worries about American leadership in NATO are unusual, they are not unprecedented. In fact, they stretch back to NATO’s origins, and a dramatic moment that occurred 68 years ago this month. Recalling this history helps remind us what’s at stake today. It’s easy to say leave Europe’s security to Europe, but that puts peace and prosperity at risk for the United States in a way that hasn’t existed in almost seven decades.

In early February 1951, a similar debate about European security gripped Washington. Republican leaders claimed that deploying American troops to Europe to support NATO was not in the nation’s best interest. They considered it unnecessary and, even worse, action that Russia might view as provocative, risking war.

But this argument ran headlong into the era’s most admired statesman, and perhaps its most famous celebrity: Dwight D. Eisenhower. President Harry S. Truman, desperate to save his policy to bolster Europe against the Soviet threat, had asked Eisenhower to leave his post as president of Columbia University and put back on his uniform as NATO’s first military commander. Formed in April 1949, the nascent alliance was still taking shape, and it fell to Eisenhower to create a military command structure, prod European nations to rebuild their militaries and galvanize American support to send U.S. troops to Europe.

These were all daunting challenges. Yet the question of whether the United States should assume the lead in NATO and deploy significant forces proved politically explosive, especially for Republicans, who had suffered in the political wilderness for 20 years. Sen. Robert A. Taft (Ohio), who was widely considered the Republican front-runner for president in 1952, had spoken out against a significant U.S. role in NATO. The only living former Republican president, Herbert Hoover, also argued forcefully against NATO, and against Eisenhower’s appointment itself, appearing on national television and testifying before Congress to call for the end of U.S. military aid and troop commitments to Europe. These arguments proved appealing to many war-weary Americans who justifiably asked: Why us, and why now?

With Eisenhower’s unique credibility and stature, it was his task to push back against this formidable wave of opposition. He was a strong advocate for what was then described as the “enlightened self interest” of American leadership in the alliance. And his campaign to save NATO demonstrated the political skill that would soon enough land him in the White House.

For three weeks in January 1951, he toured Europe to meet with key leaders and assess the situation. Then he traveled to Washington to make his case in dramatic fashion. On Feb. 1, he appeared before both houses of Congress in a packed auditorium at the Library of Congress, while reporters recorded his words to be printed in full in the next day’s newspapers.

Observers noted a change in Eisenhower. The last time he had spoken in that hall, during World War II, he seemed tentative and stuck to his script. Now, with victory behind him and projecting fame, he exuded quiet confidence. Speaking extemporaneously from a few notes, Eisenhower succinctly outlined the security challenges in Europe and the stakes involved.

He issued an impassioned plea for U.S. leadership in NATO and for a robust military presence in Europe, imploring Congress not to forget the “strength of America” and what could be achieved “when we bind that up heart and soul in material ways with our friends overseas.” However, Eisenhower was not blind to the war-weariness of the American public or the skepticism among large swaths of Americans about overseas commitments. He made clear this was not the United States' problem alone. The Europeans needed to step up as well, so the United States was not “merely an Atlas to carry the load on its shoulder.”

But while Europe needed to contribute more, the stakes for the United States could not be clearer: The “cost of peace is going to be a sacrifice ... individually and nationally.”

Eisenhower’s stirring words conveyed a sense of confidence and conviction about American leadership, and they effectively neutered the rising opposition to NATO. James Reston, one of the most influential journalists of the time, wrote in the New York Times that Eisenhower’s performance “transcend[ed] that of the Secretary of State or president.” His “combination of knowledge, experience and achievement” made it hard for “even the most cynical congressman [to] dismiss him with a wisecrack,” Reston wrote. In an editorial praising Eisenhower’s message, the Times observed that “faith in America is the principal inspiration prompting other nations to do their best to match our own exertions.”

Eisenhower understood that his performance turned the tide, as GOP-led efforts to limit the United States’ ability to support NATO fizzled. Eisenhower then tried to capitalize on his momentum. Shortly after his speech, he privately offered Taft a grand bargain: If the senator would agree to support a strong NATO and a leading U.S. role in Europe, Eisenhower would publicly vow not to run for president in 1952. Taft refused, instead choosing to carry on his fight against the kind of U.S. leadership that Eisenhower advocated. That decision proved fateful: In 1952, Eisenhower challenged Taft for the Republican nomination and won the White House.

This episode came at a pivotal moment for the alliance. If Eisenhower had faltered and Taft’s forces prevailed, it is hard to see how NATO, then new and fragile, would have sustained enough U.S. political support to survive.

For Eisenhower, that presented a profound threat. He saw U.S. security as inextricably tied to Europe’s, and feared that the United States could lose the will to act. As he argued in his speech, the country had arrived at a “decade of decision,” asking, “What nation is more capable, more ready, of providing this leadership than the United States”?

Eisenhower saw how seductive the isolationist views promoted by Taft and Hoover could be. But he was deeply frustrated by what he considered their irresponsibility — which was why he chose to return to service. “God knows I’d personally like to get out of Europe and I’d like to see [the] U.S. able to sit at home and ignore the rest of the world!” the general lamented in his diary in March 1951. “What a pleasing prospect — until you look at the ultimate consequences — destruction.”

Back then, Eisenhower won the argument. Today, we must fight the battle anew with a Republican president echoing the exact arguments used against NATO nearly seven decades ago. Just imagine how things could have gone differently if Taft had been armed with a Twitter account, or if Eisenhower had decided to stay out of uniform in his comfortable perch at Columbia.

Now, as we approach NATO’s 70th anniversary this spring, we must again look to Congress to embrace this mission in even tougher circumstances, against a commander in chief who seems oblivious to this past and determined to destroy it. Unfortunately, there is no Eisenhower to help make the case.