The wisdom of Josh Barro

Unfortunately, it’s also possible (as many other voices on Wall Street are warning) that a default would permanently raise Treasury spreads, drive investors to find alternative safe havens, cause a double-dip recession, and unleash various other evils. So, if they are willing to create the possibility of a default, Republicans in Congress are willing to expose America to severe downside risk.

It’s important to step back and consider the stakes here. Republicans say it is important, above all else, to rein in federal government spending. But the risk with excessive spending is not that government will literally become unaffordable or that we will be unable to service our debts. The United States has tremendous available fiscal capacity, as demonstrated by significantly higher tax burdens in most other first-world countries. The real risk of elevated spending is that we’ll adopt a permanently higher level of taxation.

That is a risk, but not a catastrophic one. While there is a link between government spending and economic growth, it is not as strong as conservatives like to believe. For example, Mueller and Stratmann find that a one percentage point rise in government spending as a share of GDP will tend to reduce annual GDP growth by a bit under one-twentieth of a percentage point. If we take Simpson-Bowles as an example of the sort of deficit deal that might be achieved in the medium term without the need to flirt with a bond default, then we’re talking about a difference of one to two points of GDP in government spending compared to an all-Republican plan.

There is also nothing special about government spending as a share of GDP as opposed to other determinants of economic growth, such as rule of law, freedom of contract, immigration policy, free trade and the structure of the tax code—not to mention policies on infrastructure, land use and education. Basically, we could make up a sub-0.1 percentage point hit to long term GDP growth with policy improvements elsewhere.

Which is to say, it does not make sense to create a risk that U.S. Treasuries will be dislodged as the world’s safe-haven investment as a strategy to shift the size of government by a percentage point of GDP or two. Winning this fight is not so important that it makes sense to throw caution to the wind, but that is what Republicans in Congress appear willing to do. The gamble looks even worse when you consider that a debt-limit-impasse-gone-wrong would not necessarily lead to Republicans getting their way on the long-term fiscal adjustment.

The full post is here.