Alan Greenspan oped in WSJ - “Don't be fooled by today's low interest rates

  Don't be fooled by today's low interest rates. The government could very
quickly discover the limits of its borrowing capacity… I grant that low long-term interest rates could continue
for months, or even well into next year. But just as easily, long-term rate increases can emerge with
unexpected suddenness. Between early October 1979 and late February 1980, for example, the yield on the
10-year note rose almost four percentage points.” WSJ