Aprimary factor fueling the long economic boom from world war ii to the 1970s was

 low energy cost

Energy cost was very important for the economy because the economy relied on industries that required efficient sources of energy to boost productivity. with low cost sources of energy such as oil, there was increased productivity and returns, as well as less expenditure on household energy consumption.

The case was a u.s. supreme court decision that defined the scope of the u.s. congress's legislative power and how it relates to the powers of american state legislatures. the dispute in mcculloch involved the legality of the national bank and a tax that the state of maryland imposed on it.