President Wilson first countered by meeting with individual senators, and then by subjecting himself to a grilling by the Foreign Relations Committee, which he invited to the White House. When these moves failed to budge the other side, he waged his own public opinion campaign with a whirlwind speaking tour that took him to the West Coast and back. He gave more speeches in a shorter time than he had ever done before, even during his presidential campaigns. Wilson’s big crowds and enthusiastic reception rattled Lodge, and some observers speculated about how the president might bargain with the Senate when he returned with a wind at his back.

That was not to be. Wilson’s health broke down two-thirds of the way through the tour, and he was rushed back to the White House, where he suffered a stroke that left him paralyzed on his left side. The stroke, soon followed by an unrelated but life-threatening infection, left Wilson isolated, physically debilitated, emotionally fragile and incapable of rendering sound political judgments. The White House, at the direction of his wife, Edith, issued misleading reports that the president was suffering from “nervous exhaustion” and would soon recover. Democratic senators refused to negotiate on their own, and when Wilson was able to pay attention, he spurned all compromise.

As a result, on Nov. 19, a coalition of Democrats and 15 irreconcilables voted down consent with those reservations, while the Republicans joined with the irreconcilables to vote it down without reservations. A better sense of how senators stood on the basic question of approving the treaty and league in some form came on a procedural measure to complete the debate. Sixty-three of them — just one short of the two-thirds needed for consent — voted “yea.” Whether any others might have been persuaded to join them by a still-healthy Wilson remains an intriguing question.

“Of course I am sorry to have my reservations beaten,” Lodge said the next day. If he was, he masked his sorrow well. Not just his enjoyment at the Longworths’ party but his course during the coming months seemed to belie any real regrets. He did not initiate but did briefly condone compromise bipartisan talks that might soften the reservations, but he aborted that effort when the irreconcilables threatened a party revolt. Since several of them, such as William E. Borah of Idaho and Hiram Johnson of California, were notorious for their insurgency, this was no idle threat.

Wilson likewise rejected any compromise efforts, calling Lodge and the reservationists “nullifiers.” That word, which harked back to John C. Calhoun and the slaveholding South, was sure to draw blood from Republicans just a little over half a century after the Civil War. Four months after the first votes, on March 19, 1920, the Senate voted a last time on consent with the Lodge reservations and an additional reservation calling for Irish independence. This time, 23 Democrats voted “yea,” for a total of 49 in favor, with 35 against — a majority, but seven votes short of the necessary two-thirds. It was a sad end to what Wilson had called “this great fight for the League of Nations.”

The Republicans under Warren Harding and his successor, Calvin Coolidge, are often depicted in history books as isolationists, but that’s not quite right.