Complex sentence: At one point prior to World War II, Robert Moses proposed a bridge across the harbor, with a base located on Governors Island; the intervention of the War Department under Franklin D. Roosevelt quashed the plan as a possible navigational threat to the Brooklyn Navy Yard.
Split into simpler sentences: At one point prior to WWII, Robert Moses proposed a bridge across the harbor, with a base located on Governors Island. The intervention of the War Department quashed the plan as a possible navigational threat to the Brooklyn Navy Yard.