If excessive optimism in the upswing can be resisted and inflation can be kept in check, there is a good chance that such sharp downturns can be avoided. Good, forward-looking and far-sighted policy can reduce the amplitude of cycles and lengthen them.
The seven-year upswing which started in 1982 (with a “pause that refreshes” in 1986) should not be regarded as the norm: it can be exceeded. The current upswing has, already, lasted almost as long and seems to have a fair bit of life left in it yet.