The Federal Reserve has one trump card, and that is, “you can’t force us to do anything”, former Fed chief Alan Greenspan said in an interview reflecting on his time at the central bank.

If you have to work with the executive branch, “it is very simple. There is a simple word that has got two letters in it – it’s called ‘N-O’”, he said.

In publishing a wealth of interviews with former senior officials, the Fed has revealed important details of how it deals with government – co-operatively or