The war also helped advocates of prohibition. The spirit of wartime sacrifice, in particular the need to conserve food, delivered new support to opponents of making and consuming alcoholic beverages. Prohibitionists also played on nativism, arguing that "disloyal" Irish and German immigrants wasted valuable American resources by drinking gallons of whiskey and beer. And the Progressives' efforts to clean up the corrupt saloon politics received a boost from a war effort cast as a crusade for good government everywhere. Congress responded to the well-organized temperance lobby by passing a temporary ban on the production of intoxicating liquids in the summer of 1917. In January 1919, the Constitution was amended to make the ban permanent.