The history of historic preservation in the United States is still being written and debated, and several seminal events have been identified as the cathartic moment in which the United States awoke to take stock of and appreciate its collective natural and historic treasure. However, there is little consensus as to which event is most representative of when the preservation movement gained a foothold in America, and became a conscious field of study and activism. Some experts trace the first empowered moments of preservation to the work of the Mount Vernon Ladies Association of the Union, who successfully purchased and stewarded Washington's home following the refusal of the state and national governments to purchase the property. Other scholars point to the protest over the demolition of New York's Penn Station in 1963 as the moment when the public became involved in preservation and its perception of development and progress in America began to shift. Finally, some cite the importance of the federal government's involvement, whether it be through the creation of the National Park Service in 1916 or the passage of the National Historic Preservation Act of 1966.