Compared to laying siege to government, hurting millions, and putting the economy at risk, it’s only a minor irritant, I suppose, one of the dozens of little misrepresentations that we are so used to hearing from the right wing that we just shrug our shoulders and wait for something new. But the fact the media almost never pushes back suggests that letting it slide is a mistake. And it’s just fractions!

Remember third grade math? Sure you do. It’s when you probably first learned fractions. Numerators! Denominators? Percentages! Pies! Well, it seems many right wingers skipped that year, because they can’t recall that a fraction has both a numerator and a denominator, so the size of the fraction depends on both.

So night after night, apparent third grade dropouts tell news anchors and talk show hosts, none of whom even sighs (sigh), that government spending has exploded under Socialist Obama. Before Obama, it was about 19 percent of GDP or 1/5th. But now its almost 1/4th, or 24 percent of GDP.

Tom Coburn said that on my public tv. Boehner and McConnell and Kyl say that. Every Tea-GOP and rightwinger has it tatooed on their foreheads, and Sarah Palin has is written on her palm. From 19 to 24 percent! Yikes!

Here’s Professor Krugman dragging us back to third grade with The Truth about federal spending:

The fact is that federal spending rose from 19.6% of GDP in fiscal 2007 to 23.8% of GDP in fiscal 2010. So isn’t that a huge spending spree? Well, no.

First of all, the size of a ratio depends on the denominator as well as the numerator. GDP has fallen sharply relative to the economy’s potential; here’s the ratio of real GDP to the CBO’s estimate of potential GDP:

Krugman goes on to use actual data related to the denominator. Facts! math! Annoying. How does he remember this complicated stuff?

He then shows that the remaining increase in the numerator is due almost entirely to reduced revenues and higher safety net spending caused by the recession, plus temporary stimulus spending, also necessitated by the recession, that’s now phasing out.

Bottom line. No permanent increase in the size of government. It’s the recession, not due to Obama. And Republicans either don’t know third grade math or they’re just lying.

We all know this, but it’s still stunning, and disheartening, that an entire party can be that dishonest and get away with this nonsense night after night.

Update: Mark Thoma of the Economist’s View finds David Frum also stunned by the Wall Street Journal’s denial of elementary math.

If you were to write a story about government debt, you’d probably be inclined to write about the two sets of government decisions that produce deficits or surpluses: decisions about expenditure and decisions about revenue. You’d want to do that not only as a matter of fairness, but also as a matter of math.

And that’s why, my friend, you would wash out as a WSJ editorialist. They wrote this editorial without any reference to revenues whatsoever. Boom! Gone! Don’t deny reality. Defy reality. . . .

One of the many traps and impediments facing a Journal editorialist writing about debt is that up until 2009, the US debt burden rose most under the two presidents the Journal most ardently supported: Ronald Reagan and George W. Bush. The debt burden declined most under the presidents the Journal most despises – Dwight Eisenhower, Bill Clinton and Jimmy Carter.

Math has a well known liberal bias.