What was the significance of the decision that a state could not tax the first bank of the united states?

In 1791, The First Bank of the U.S was one of the 4 major financial innovations proposed and supported by Hamilton,The First Secretary of the Treasury. In addition to the national bank, the other measures were assumption of the state war debts by the U.S. Government, establishment of a mint and imposition of a federal excise tax. 

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