Jackson authored the National Environmental Policy Act, which has been called one of the most influential environmental laws in history. It helped to stimulate similar laws and the principle of publicly analyzed environmental impact in other states and in much of the world. Jackson was also a leader of the fight for statehood for Alaska and Hawaii. In 1974, Jackson sponsored the Jackson-Vanik amendment in the Senate (with Charles Vanik sponsoring it in the House), which denied normal trade relations to certain countries with non-market economies that restricted the freedom of emigration. The amendment was intended to help refugees, particularly minorities, specifically Jews, to emigrate from the Soviet Bloc. Jackson and his assistant, Richard Perle, also lobbied personally for some people who were affected by this law such as Anatoly (now Natan) Sharansky.