One hundred years ago, on Nov. 19, 1919, Alice Roosevelt Longworth threw a late-night party. Longworth, the daughter of Theodore Roosevelt and wife of Nicholas Longworth, the future speaker of the House, was celebrating the defeat in the Senate that day of the Treaty of Versailles, which encapsulated President Woodrow Wilson’s grand project for world peace, the League of Nations. “We were jubilant,” she recalled later, “too elated to mind the reservationists. And by we, I mean the irreconcilables, who were against any League, no matter how ‘safeguarded’ with reservations.”

Oddly, the party’s de facto guest of honor was the Senate’s reservationist in chief, Henry Cabot Lodge of Massachusetts, the Republican leader and chairman of the Foreign Relations Committee. Lodge was critical of the treaty, but not outright opposed — not one of Longworth’s “irreconcilables.” His committee had attached a number of statements — “reservations” — to the Senate’s advice and consent to the treaty, defining and limiting America’s obligations under it.

Still, those reservations were enough to deadlock debate on the treaty, blocking Senate approval. Lodge entered the history books as the man who sank American participation in the League of Nations — and led to a retreat from international leadership, at a time when, many historians argue, the world needed America to take such leadership.

Though Lodge claimed publicly that he was pleased to see the treaty go down in flames, he could not have been happy with the results. Lodge was many things, but he was no isolationist. Across his 40 years in Congress, he had advocated for what he called a “large policy” — an expansive foreign agenda that would allow his nation to assume its proper place as a great power. Early on, he had disparaged the country’s traditional isolation as a “habit” that had outlived its usefulness. Even when he began to reject Wilson’s vision of internationalism, Lodge protested that he had no “superstitious regard” for George Washington’s and Thomas Jefferson’s bans on permanent and entangling alliances.