During the 1912 campaign, accusations that Roosevelt was a drunkard began surfacing, though entirely unfounded. Roosevelt argued that this accusation was merely campaign slander and untrue, but his protestations had little effect. He privately determined that if this lie was ever printed, he would squelch it once and for all. On October 12, 1912, the newspaper Irong Ore in Ishpeming, Michigan made the mistake of printing that Roosevelt was a heavy drinker and frequently issued torrents of "lies and curses" when drunk. Roosevelt kept his personal vow and immediately filed a lawsuit for libel against the paper's editor, George S. Newitt. During the trial–held in Marquette, Michigan, in May 1913–scores of witnesses testified that Roosevelt abstained from heavy liquor and beer and drank only an occasional glass of wine with meals. Newitt was unable to produce a single witness to support his article's claim, and he offered a retraction and apology. The court assessed damages at six cents and adjourned the case.
Within months after his victory in the courtroom, Roosevelt set out on his last great adventure abroad. As a boy and young man he had seen Europe, Egypt, and the Middle East. In his middle years he took in Cuba and Panama, and after his presidency he explored Africa. The final test of his endurance and strength was the Amazon River. After a brief tour of several of the most prestigious South American universities, Theodore Roosevelt set out for southern Brazil in 1913 with his son Kermit to collect rare specimens for New York's Museum of Natural History and to explore the uncharted River of Doubt in the Amazon basin. The 1000-mile journey upriver was both thrilling and perilous. The team of explorers was entirely alone in the jungles for months at a time, and many of the humans they did encounter were hostile natives. One of the porters died in the river's rapids and another went insane before stealing food, murdering another porter, and running off into the jungle. Roosevelt himself nearly met his end when he re-injured the leg he had hurt in the carriage accident in 1902, and then contracted jungle fever and could not be moved. Roosevelt begged to be left alone in the jungle so that the others could escape, but his son would not listen and continued to care for his father. When the explorers returned to New York in May of 1914, Roosevelt had lost thirty-five pounds. For his efforts, the River of Doubt was renamed the Rio Teodoro.
Roosevelt spent a couple of years recuperating from the excitement of the Brazilian adventure, but jumped back into the thick of things in 1915 when a German U-boat sank the British ship Lusitania and killed over 1,100 people, 114 of which were American. Since 1914, the powers of Europe had been battling each other in the Great War, now known as World War I. When war was first declared, President Wilson advocated total neutrality for the United States, and for a while many Americans agreed with him. The sinking of the Lusitania, however, caused many Americans–including Roosevelt–to doubt Wilson's position. Just as he had in his book A History of the Naval War of 1812 and as Assistant Secretary of the Navy, Roosevelt once again crusaded for military preparations. In a series of articles, he called for a massive military buildup and permanent military conscription for all young American men. He repeatedly denounced President Wilson for his unwillingness to fight and impatiently called for entering the war immediately on the side of Britain and France to fight Germany. Although many Americans considered Roosevelt's call to arms a bit overzealous, his efforts did help prepare the nation for the war they would eventually fight.
President Wilson changed his tune when Germany began dictating which shipping lines the United States could and could not use in the Mediterranean and North Seas. On April 2, 1917, the recently reelected Wilson declared war on Germany. Roosevelt, excited at the prospect of a righteous war against the immoral and unjust Germany, immediately rushed to Washington to see Wilson and to request permission to organize and lead a volunteer combat unit similar to his Rough Riders in the Spanish-American War. Wilson, though amused, did not grant the old Colonel his request.
Although Roosevelt was unable to fight in Europe, he was fiercely proud of his four sons who joined the military and fought against Kaiser Wilhelm II. All served with bravery and distinction. Ted commanded an infantry regiment, was wounded, and received the Distinguished Service Cross. Kermit earned the British Military Cross, and Archibald was awarded the French Croix de Guerre. The youngest, Quentin, served as a combat pilot until July 14, 1918, when he was killed in action, shot down by two German planes behind enemy lines. The news of Quentin's death shook Roosevelt to his core. Many of his friends claimed that Roosevelt lost his energy and boyish exuberance and never regained it. Quentin quickly became a symbol for all young American men who died in service, and the nation joined Roosevelt in his mourning.
Quentin's death marked the beginning of the end for Roosevelt. When the war eventually ended and the world was celebrating Armistice Day on November 11, 1918, Roosevelt was undergoing surgery to once again drain abscesses that had developed on his bad leg. He also suffered from rheumatism and remained in bed for the last several months of 1918. He was eventually admitted to Roosevelt Hospital in New York, where he remained for seven weeks. Doctors warned him that he would probably be confined to a wheelchair for the remainder of his days.