linguistic:paraphrasing
Paralytic illness and political comeback (1921–1928)

Roosevelt sought to build support for a political comeback in the 1922 elections, but his career was derailed by an illness. It began while the Roosevelts were vacationing at Campobello Island in August 1921. His main symptoms were fever; symmetric, ascending paralysis; facial paralysis; bowel and bladder dysfunction; numbness and hyperesthesia; and a descending pattern of recovery. Roosevelt was left permanently paralyzed from the waist down and was diagnosed with polio. A 2003 study strongly favored a diagnosis of Guillain–Barré syndrome, but historians have continued to describe his paralysis according to the initial diagnosis.

Though his mother favored his retirement from public life, Roosevelt, his wife, and Roosevelt's close friend and adviser, Louis Howe, were all determined that he continue his political career. He convinced many people that he was improving, which he believed to be essential prior to running for office. He laboriously taught himself to walk short distances while wearing iron braces on his hips and legs, by swiveling his torso while supporting himself with a cane. He was careful never to be seen using his wheelchair in public, and great care was taken to prevent any portrayal in the press that would highlight his disability. However, his disability was well known before and during his presidency and became a major part of his image. He usually appeared in public standing upright, supported on one side by an aide or one of his sons.

Beginning in 1925, Roosevelt spent most of his time in the Southern United States, at first on his houseboat, the Larooco. Intrigued by the potential benefits of hydrotherapy, he established a rehabilitation center at Warm Springs, Georgia, in 1926, assembling a staff of physical therapists and using most of his inheritance to purchase the Merriweather Inn. In 1938, he founded the National Foundation for Infantile Paralysis, leading to the development of polio vaccines.

Roosevelt remained active in New York politics while also establishing contacts in the South, particularly in Georgia, in the 1920s. He issued an open letter endorsing Al Smith 's successful campaign in New York's 1922 gubernatorial election, which both aided Smith and showed Roosevelt's continuing relevance as a political figure. Roosevelt and Smith came from different backgrounds and never fully trusted one another, but Roosevelt supported Smith's progressive policies, while Smith was happy to have Roosevelt's backing.

Roosevelt gave presidential nominating speeches for Smith at the 1924 and 1928 Democratic National Conventions; the speech at the 1924 convention marked a return to public life following his illness and convalescence. That year, the Democrats were badly divided between an urban wing, led by Smith, and a conservative, rural wing, led by William Gibbs McAdoo. On the 101st ballot, the nomination went to John W. Davis, a compromise candidate who suffered a landslide defeat in the 1924 presidential election. Like many, Roosevelt did not abstain from alcohol during Prohibition, but publicly he sought to find a compromise on the issue acceptable to both wings of the party.

In 1925, Smith appointed Roosevelt to the Taconic State Park Commission, and his fellow commissioners chose him as chairman. In this role, he came into conflict with Robert Moses, a Smith protégé, who was the primary force behind the Long Island State Park Commission and the New York State Council of Parks. Roosevelt accused Moses of using the name recognition of prominent individuals including Roosevelt to win political support for state parks, but then diverting funds to the ones Moses favored on Long Island, while Moses worked to block the appointment of Howe to a salaried position as the Taconic commission's secretary. Roosevelt served on the commission until the end of 1928, and his contentious relationship with Moses continued as their careers progressed.

In 1923 Edward Bok established the $100,000 American Peace Award for the best plan to deliver world peace. Roosevelt had leisure time and interest, and he drafted a plan for the contest. He never submitted it because Eleanor was selected as a judge for the prize. His plan called for a new world organization that would replace the League of Nations. Although Roosevelt had been the vice-presidential candidate on the Democratic ticket of 1920 that supported the League, by 1924 he was ready to scrap it. His draft of a "Society of Nations" accepted the reservations proposed by Henry Cabot Lodge in the 1919 Senate debate. The new Society would not become involved in the Western Hemisphere, where the Monroe doctrine held sway. It would not have any control over military forces. Although Roosevelt's plan was never made public, he thought about the problem a great deal and incorporated some of his 1924 ideas into the design for the United Nations in 1944–1945.