James Montgomery Flagg: Beware the Wrath of a Patient Man 1918. Hands on hips and jaw set, Uncle Sam, the familiar self-portrait Flagg devised for I Want You, demands that we buy War Savings Stamps. Flagg later claimed he painted himself in the mirror as Uncle Sam to save the price of hiring a model. One of the most elusive, if not the most elusive, of the Flagg World War I posters. 30×20 near mint, conservation backed.