Comment: "Such rates have only been seen during the Civil War and the Volker era "

Hahaha!  No, not even close.  7% is not outrageous, it is quite normal and within the average historical range.  Unless you think the Civil War happened in 1990 (7%) or 1989 (8%), or perhaps the year before when it was 9.75%?.  

At 10% interest rates that is 2 trillion going to interest alone.  That is more than half of the federal budget.  So in any scenario, whoever raises the interest rates (to WHATEVER you would agree is the "historical average, because it damn sure isn't zero) will crash the economy and you have basically no counter-argument whatsoever.  None.