The Senate Killed the Versailles Treaty and Conservatives Should Know Why

On November 19, 1919, the United States Senate voted down the treaty that ended the First World War, and then voted it down again, and then went home. The history textbooks have a one-word explanation for this: isolationism. It is neat, it is easy to grade and it is badly incomplete.

The Senate that killed the Versailles Treaty included men who wanted an international organization, men who wanted a different one, and a pair of stubborn presidents, one in the White House and one in the Foreign Relations Committee, who could not be persuaded to settle. Behind all of it sat a constitutional question that is still ours: who decides when the United States goes to war, and can a treaty take that decision away from the people's representatives?

The setting: a victory with a bill attached

The armistice came on November 11, 1918. President Woodrow Wilson went to Paris and spent months negotiating the settlement. He had set out his program in the Fourteen Points of January 1918, and the fourteenth called for a general association of nations. That association became the League of Nations, and its Covenant was written into the Treaty of Versailles itself, so that anyone who voted for the peace voted for the League.

The Constitution is clear about what comes next. Article II, Section 2 gives the president the power "to make Treaties, provided two thirds of the Senators present concur." The Senate is not a rubber stamp. It was designed by the Framers as the check on exactly this kind of agreement, and the two-thirds rule was set high on purpose: a treaty binds the nation as supreme law under Article VI, so the Framers wanted a supermajority before it could do so. Wilson knew that. He chose not to build a coalition for it in the chamber he would need.

He did not put a prominent Republican on his delegation in Paris. The Republicans had won the Senate in the 1918 midterms. The Foreign Relations Committee was chaired by Henry Cabot Lodge of Massachusetts, a Harvard historian by training and a senator since 1893, who disliked Wilson personally and distrusted the League on principle. If you wanted to design a negotiation that would fail, you could hardly improve on it. It was like sending a team to a big game after sacking the half of it that might have to carry the ball.

What Article X said

The heart of the dispute was one article of the Covenant. Article X read:

The Members of the League undertake to respect and preserve as against external aggression the territorial integrity and existing political independence of all Members of the League.

It went on to say that in case of aggression or threat, the Council would advise on how the obligation should be fulfilled. To Wilson, Article X was the moral center of the League: an end to conquest by common pledge. To Lodge, it was something else. It looked like a standing commitment to defend the borders of every member, anywhere, forever, with the decision on how to honor it taken by a council in Geneva and the United States left to follow.

That is a constitutional objection, not an isolationist one. Under Article I, Section 8, Congress has the power to declare war. If a treaty obliged America to go to war in some distant boundary dispute, either the obligation was binding, and the war power had been effectively moved to an international body, or it was not binding, and the pledge was a bluff that would humiliate America when called. Lodge said that a promise you do not intend to keep, or cannot keep without a vote that may not come, is worse than no promise at all.

Wilson's tour

Wilson took the argument to the country. In September 1919 he set out on a railway tour of the West, a trip of some 8,000 miles in about three weeks, to rally public opinion and pressure the Senate. He was exhausted before he began. On September 25 he spoke at Pueblo, Colorado, and collapsed that night. On October 2, back in Washington, he suffered a severe stroke that left him incapacitated for weeks and diminished for the rest of his term.

This detail is not a footnote. The man who needed to compromise could not negotiate, and those around him could not tell him how far the votes had slipped. A republic is run by processes, but it is carried out by people, and the people were not up to it.

The Lodge reservations

Lodge had a plan, and it was subtler than his reputation. He did not move to kill the treaty. He moved to attach reservations: conditions that the United States would accept as part of its ratification. The committee eventually produced fourteen of them, an unsubtle echo of Wilson's own Fourteen Points. Among them were these:

• The United States would keep for itself the judgment of whether it had fulfilled its obligations under the Covenant, including when it chose to withdraw.
• The United States assumed no obligation to preserve the territorial integrity or political independence of any other country, or to interfere in controversies between nations, unless Congress, in any particular case, should by act or joint resolution so provide.
• Domestic questions, including immigration and tariffs, were reserved to the United States alone, and the Monroe Doctrine was declared outside the League's reach.

Look at the Article X reservation. It did not say America would never help. It said America would help when Congress decided to. In constitutional terms it was almost a restatement of Article I, Section 8: the war power stays where the Constitution put it. A conservative who thinks the Constitution means what it says should find nothing radical in that. It is the sort of thing a modern senator would call "reserving Congress's prerogatives" and expect applause.

The factions

The Senate was not divided into two camps but into several, and the numbers matter.

1. The strong internationalists. Mostly Democrats, loyal to Wilson, willing to accept the Covenant as written.
2. The mild reservationists. Republicans and some Democrats who wanted the League with the reservations and would have voted yes.
3. The strong reservationists, led by Lodge, who wanted tougher conditions.
4. The irreconcilables, among them William Borah of Idaho and Hiram Johnson of California, who opposed the League in any form. They were a small band and a loud one, and they were the ones who made the later "isolationist" label stick.

The arithmetic is what makes the story tragic. The mild reservationists and the Democrats together could have supplied the two-thirds, if the Democrats had accepted the reservations. Wilson told them not to.

The votes of November 1919 and March 1920

On November 19, 1919, the Senate first voted on the treaty with the Lodge reservations attached. The vote was 39 in favor and 55 against. Most Democrats, following Wilson's instruction, voted against the treaty with the reservations, and they were joined by the irreconcilables who opposed it either way. Then the Senate voted on the treaty without reservations, which Wilson wanted, and that was defeated too, 38 to 53. The two sets of "no" votes came from opposite sides of the argument, and between them they sank the treaty.

The country was not content to leave it there. Public pressure, and a sense that peace should be ratified, led to a second attempt. In early 1920 the Senate returned to the treaty. On March 19, 1920, the vote on ratification with reservations was 49 in favor and 35 against. That is a majority of the Senate, and the treaty still failed, because two-thirds of the senators present were required. A number of Democrats had voted yes in defiance of Wilson, which showed how close it came, and how much of the blame belongs to the president's refusal.

Wilson's reasoning is worth stating fairly, because it was not frivolous. He believed the reservations would gut the League and invite the other powers to demand their own, unraveling the whole settlement. He believed in the moral force of the original text. He also believed, in the manner of a man who had been right about some great questions, that history would vindicate him.

The steelman: what the internationalists got right

The strongest case for the League deserves a fair statement. The First World War had cost millions of lives and had grown out of a system of alliances and ultimatums that nobody controlled. A collective-security pledge, with the United States inside it, might have deterred later aggression. The League without America was weak, and its weakness showed in Manchuria, Abyssinia and the Rhineland. Many historians have argued that an American seat at the table in the 1920s could have changed the course of the next decade.

That is a serious argument, and I will not pretend otherwise. Here is the answer, in four points.

1. A pledge that Congress cannot honor is not a pledge. The reservations did not reject collective security. They required that the decision be made by the body the Constitution authorizes. A deterrent works only if the adversary believes you will act, and an adversary can believe a nation more easily when its commitments have been ratified by the people who must keep them.
2. The League's weakness did not come only from American absence. Britain and France, the two leading members, were unwilling to enforce the Covenant against powerful violators, and the enforcement tools were slow and unanimous-vote machinery. America's presence would not have changed the structure.
3. The two-thirds rule exists to force broad consent. If a treaty cannot gather two-thirds, it lacks the national consensus a binding supreme-law commitment requires. The Framers wanted treaties to be hard to make for precisely this reason.
4. The responsibility for the failure was shared. A president who could have accepted modest reservations chose to lose everything rather than win most of it. A leader who insists on all or nothing should not be surprised when the answer is nothing. It is the one forecast in politics that comes in on time.

"Isolationist" is the wrong word

Let me press the point, because the label has done damage. Lodge was no isolationist. He had supported American expansion in the 1890s, advocated a strong navy, and wanted America to play a large role in the world. The fight, in other words, was about the League's machinery and not about a general retreat. What he opposed was an open-ended commitment run by a standing council, one that would shift the decision from the Senate and the House to a table in Geneva.

The irreconcilables were closer to the label, but even they argued from the Founding. They cited Washington's warning against permanent entanglements, which is a view worth understanding on its own terms, as told in What Washington's Farewell Address Really Said About Foreign Entanglements. A person can reject the policy and still admit that it comes from a constitutional tradition, not a failure of nerve.

So the proper summary is this. The Senate did not reject engagement with the world. It rejected a transfer of the war power. It was a fight about who holds the sword, and the Constitution says Congress holds it.

What came after

The United States made its own peace. In 1921, after Warren Harding took office, Congress passed a joint resolution declaring the war with Germany at an end, and the president signed it, and a separate peace treaty with Germany followed that year. America never joined the League. It did take part in conferences on naval limitation and, later, in the Kellogg-Briand Pact, but it held back from any standing commitment.

The aftermath is a lesson in humility for everyone. The League failed to stop the aggression of the 1930s, and America's absence was one factor among many. America was also badly unprepared when the next war came. A fair reading says that both sides of the 1919 argument were partly right, and that the tragedy lay in the inability to reach a compromise that would have given the country a binding commitment and a congressional veto at once. That is a hard thing to build, and it is the very work the Senate exists to do.

What the Treaty Clause teaches

There are lessons for the present that do not depend on how you feel about any particular alliance.

• Treaties bind the nation as supreme law. Article VI says they are, with the Constitution and federal statutes, "the supreme Law of the Land." A commitment that serious should clear a high bar, and two-thirds is the bar.
• The Senate shares the treaty power, which means the president cannot do it alone. A president who wants to bind the nation to a long-term obligation needs to bring senators in at the start, not at the end.
• Executive agreements are not a substitute. Presidents have increasingly used agreements that never go to the Senate to do what treaties once did. A conservative who takes the two-thirds rule seriously should be suspicious of every device that avoids it, including politically significant deals with foreign governments. The principle is the same everywhere: significant commitments need public, accountable consent.
• Alliances can be good, and they can be written to respect Congress. The North Atlantic Treaty, approved by the Senate in 1949, contains in Article 5 a pledge that each party will take "such action as it deems necessary," the very language that preserves each country's own constitutional process. Read the treaty for yourself in Read the North Atlantic Treaty, All Fourteen Articles Take Ten Minutes. It is worth noting how closely Article 5 resembles the Lodge reservation to Article X.

That last comparison deserves a moment. The Senate of 1949, after a second world war, approved a collective-defense treaty that left the final decision with each member's constitutional process. It is not hard to argue that the Lodge approach, adopted a generation earlier, would have given the country a League it could actually keep its word to. The idea that a binding alliance and a congressional check are opposites is false. The best alliance in history was built with both.

A word about the opposing historical memory

You will hear, and you may have been taught, that Lodge and the Republicans were petty men who sank world peace out of spite. Personal dislike was real on both sides, and it would be silly to deny it. But a constitutional argument does not become wrong because the person making it is also irritated. The reservations stand or fall on their merits, and on their merits they ask for something the Constitution already requires.

Equally, you should not swallow the opposite myth, that Wilson was a fool. He was a serious man with a serious aim, and his insistence on a general association of nations was an honest effort to prevent another catastrophe. His mistake was a political one: to treat a negotiation with a co-equal branch as if it were a sermon to be accepted.

For more on who holds the sword, see Commander in Chief Means Less Than Presidents Claim and More Than Critics Say and Letters of Marque Are Still in the Constitution and Here Is Why They Matter.

The case in brief

1. The Treaty of Versailles carried the League of Nations Covenant, and Article X pledged members to preserve each other's territorial integrity against external aggression.
2. Henry Cabot Lodge's fourteen reservations were a constitutional position: the United States would assume no Article X obligation unless Congress, by act or joint resolution, so provided.
3. After Wilson's collapse in September and his stroke in October 1919, the Senate voted 39 to 55 on the treaty with reservations and 38 to 53 without them on November 19, and fell short again on March 19, 1920, by voting 49 to 35, below the two-thirds required.
4. "Isolationism" misdescribes the fight. It was about who holds the war power, and the Senate's answer matched the 1949 North Atlantic Treaty, which left action to each member's constitutional process.
5. The two-thirds rule in the Treaty Clause exists so that binding commitments carry broad national consent, and every shortcut around it should be treated with suspicion.

What you can do: read Article II, Section 2 and Article VI at the Constitution page, then check the oversight page to see how your senators vote on treaties and nominations, and tell them what you expect.