In the Northern Hemisphere, December 21st is usually the shortest day of the year and is sometimes regarded as the first day of winter. In the Southern Hemisphere, December 21st is usually the longest day of the year and occurs during the southern summer.
As World War II began, Geisel turned to political cartoons, drawing over 400 in two years as editorial cartoonist for the left-leaning New York City daily newspaper, PM. Geisel's political cartoons, later published in Dr. Seuss Goes to War, denounced Hitler and Mussolini and were highly critical of non-interventionists ("isolationists"), most notably Charles Lindbergh, who opposed US entry into the war. One cartoon depicted all Japanese Americans as latent traitors or fifth-columnists, while other cartoons simultaneously deplored the racism at home against Jews and blacks that harmed the war effort. His cartoons were strongly supportive of President Roosevelt's handling of the war, combining the usual exhortations to ration and contribute to the war effort with frequent attacks on Congress (especially the Republican Party), parts of the press (such as the New York Daily News, Chicago Tribune, and Washington Times-Herald), and others for criticism of Roosevelt, criticism of aid to the Soviet Union, investigation of suspected Communists, and other offences that he depicted as leading to disunity and helping the Nazis, intentionally or inadvertently.
In 1942, Geisel turned his energies to direct support of the U.S. war effort. First, he worked drawing posters for the Treasury Department and the War Production Board. Then, in 1943, he joined the Army as a Captain and was commander of the Animation Department of the First Motion Picture Unit of the United States Army Air Forces, where he wrote films that included Your Job in Germany, a 1945 propaganda film about peace in Europe after World War II; Our Job in Japan; and the Private Snafu series of adult army training films. While in the Army, he was awarded the Legion of Merit. Our Job in Japan became the basis for the commercially released film Design for Death (1947), a study of Japanese culture that won the Academy Award for Documentary Feature. Gerald McBoing-Boing (1950) was based on an original story by Seuss and won the Academy Award for Animated Short Film.
Geisel's early artwork often employed the shaded texture of pencil drawings or watercolors, but in his children's books of the postwar period, he generally made use of a starker mediumpen and inknormally using just black, white, and one or two colors. His later books, such as The Lorax, used more colors.
Geisel's style was unique his figures are often "rounded" and somewhat droopy. This is true, for instance, of the faces of the Grinch and the Cat in the Hat. Almost all his buildings and machinery were devoid of straight lines when they were drawn, even when he was representing real objects. For example, If I Ran the Circus shows a droopy hoisting crane and a droopy steam calliope.
Geisel evidently enjoyed drawing architecturally elaborate objects. His endlessly varied but never rectilinear palaces, ramps, platforms, and free-standing stairways are among his most evocative creations. Geisel also drew complex imaginary machines, such as the Audio-Telly-O-Tally-O-Count, from Dr. Seuss's Sleep Book, or the "most peculiar machine" of Sylvester McMonkey McBean in The Sneetches. Geisel also liked drawing outlandish arrangements of feathers or fur: for example, the 500th hat of Bartholomew Cubbins, the tail of Gertrude McFuzz, and the pet for girls who like to brush and comb, in One Fish Two Fish.
Geisel's illustrations often convey motion vividly. He was fond of a sort of "voil" gesture in which the hand flips outward and the fingers spread slightly backward with the thumb up. This motion is done by Ish in One Fish Two Fish when he creates fish (who perform the gesture themselves with their fins), in the introduction of the various acts of If I Ran the Circus, and in the introduction of the "Little Cats" in The Cat in the Hat Comes Back. He was also fond of drawing hands with interlocked fingers, making it look as though his characters were twiddling their thumbs.
Geisel also follows the cartoon tradition of showing motion with lines, like in the sweeping lines that accompany Sneelock's final dive in If I Ran the Circus. Cartoon lines are also used to illustrate the action of the sensessight, smell, and hearingin The Big Brag, and lines even illustrate "thought", as in the moment when the Grinch conceives his awful plan to ruin Christmas.