Which US President, known for a complex and often controversial relationship with both the press and his own political party, oversaw a period of significant social and economic change, including the passage of landmark legislation aimed at environmental protection and social welfare?

1. He faced significant challenges related to a major national scandal.
2. His administration was marked by a shift in US foreign policy with a focus on opening relations with a major world power.
3. His vice president would later become his successor and also serve as president in their own right.
4. He authorized the creation of a new cabinet-level department focused on environmental protection.