The railroad and coal strike scheduled for November 1, 1919, roused Palmer. The Senate, on October 17, had already challenged him to demonstrate what action he was taking against foreign radicals. Now these two industries faced disruption as prices continued to rise and shortages threatened, even as the presidential election year of 1920 approached. The railroad brotherhoods postponed their strike in the face of political and public opposition, but the United Mine Workers under John L. Lewis went forward. Palmer invoked the Lever Act, a wartime measure that made it a crime to interfere with the production or transportation of necessities. The law, meant to punish hoarding and profiteering, had never been used against a union. Certain of united political backing and almost universal public support, Palmer obtained an injunction on October 31 and 400,000 coal workers struck the next day.