During President Madison's terms in office, nationalism grew in the United States. To compete with foreign countries and improve economic independence, Madison pursued protective tariffs and transportation infrastructure like roads and canals. This helped spur industrialization and economic development. Under later president James Monroe, nicknamed the "Era of Good Feelings", the federal government grew stronger through Supreme Court cases that enhanced its power over states. Monroe also issued the Monroe Doctrine to ward off future European colonization in the Americas and assert U.S. influence in the western hemisphere.