The recent debate about the debt limit focuses on the negative economic impact of a decision by the government not to increase the debt limit. That’s why President Obama says he is asking for clean debt limit increase—one not linked to spending reductions, saying that a default would cause economic harm, and that we should not play chicken with the American economy.
But with current high and growing debt levels a clean debt limit increase would also hurt the economy. If politicians just increase the debt limit now without reducing the rapid growth of spending, then they will be expected to do so in the future and the debt explosion will continue to create a drag on the economy with a likely future crisis. The time pattern may be different with a clean debt limit increase–if kicking the can down the road postpones the harm, but the overall impact is negative, and it could be worse if there is a debt crisis.
There is an obvious way to prevent both evils: follow a policy strategy which links debt limit increases to reductions in the growth of spending. By focusing on tactics–games of chicken, leverage and threats—Washington is ignoring this sensible policy strategy.
In a recent technical paper my colleague Bob Hall, rigorously works out the effects of severing the link between debt increases and deficit spending. He defines a parameter which he calls “alpha.” It’s simply the amount by which politicians reduce the deficit when they increase the debt, measured as a fraction of the debt to GDP ratio. In other words, alpha is an indicator of how much the government “leans against” the debt. As Bob puts it: “Alpha is all-important in the analysis….Governments with no tendency to lean against debt, with alpha = 0, face a likelihood but not a certainty of debt crisis.” The problem with a clean debt limit increase is that it effectively sets alpha to 0.
A much better value of alpha, as Bob shows, is around .1, which, if you measure spending reductions on a ten year basis, translates to .1X10 or 1, or, in other words, a strategy like the one-to-one link sometimes called the Boehner rule. So while some may think of such a rule a threat, it is really a strategy, and a sensible strategy in my view.