Which president believed in a foreign policy were other countries could not interfere with the affairs of countries?

The president who believed in a foreign policy where other countries could not interfere in the affairs of other nations was James Monroe. This principle is encapsulated in the Monroe Doctrine, established in 1823, which asserted that the Western Hemisphere was off-limits to European colonization and intervention. Monroe's policy aimed to protect newly independent nations in Latin America from European powers and emphasized American sovereignty in the region.