The American Budget Deficit.
From the paper:
Determining the correct, or economically benign, level of deficit and debt is a subject for endless debate. Economies do not operate by a simple law of cause and effect, of plus and minus, of deficit and surplus. They are complex interweaving of many economic and psychological factors, both domestic and international. Although a huge deficit is never to be praised, there are times in a nation’s life when deficits are necessary and even beneficial.