Social Democratic League of America

The Social Democratic League of America (SDL) was a short-lived American political party established in 1917 by electorally-oriented socialists who favored the participation of the United States in World War I. Led by such intellectuals as John Spargo, Emanuel Haldeman-Julius, and William English Walling, the SDL maintained effective control over the venerable socialist newspaper The Appeal to Reason (then known as The New Appeal) during 1918, the year of the group's greatest public influence.

Claiming a membership of 2,500 at its peak — a number possibly inflated — the SDL did achieve some limited success in building support for the military effort among the wavering socialists of France and Great Britain during the last weary months of the war. Following the end of the European fighting, however, the SDL lost much of its raison d'être and dissolved amidst personal acrimony — as did the National Party, a parallel political umbrella organization with which it was closely associated.

American entry into World War I came in the immediate aftermath of President Woodrow Wilson's successful November 1916 re-election campaign, which made prominent use of the slogan "He Kept Us Out of War." Just months after Wilson's resounding victory, the resumption of unlimited submarine warfare by Germany early in 1917 pushed Wilson and the United States towards intervention in the European conflict.

For its part, the Socialist Party of America (SPA) had been steadfast in its opposition to militarism and American participation in the bloodbath on the other side of the Atlantic. Throughout 1915 and 1916 the SPA had consistently put forward pacifist views in opposition to the organized campaign for so-called "military preparedness" in America.

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