It was a lot worse than that. The longshoremen's union constantly threatened to shut down the docks over which our war materiel was being shipped to the fronts. Franklin Destroyer Roosevelt made a deal with the Devil (the Mafia) to keep them open. We are still paying the price for that one.
It wasn't just here - unions in England did the same things, even when the country was on the verge of being invaded by the Nazis. There were some very bitter Tommies and Jacks in the British Army and Navy when that fact became known.