“When you add up his policies, this president has increased the national debt by five trillion dollars.”

— Mitt Romney, in Des Moines, May 15, 2012

Who’s to blame for the national debt? In a speech in Iowa, the former Massachusetts governor on Tuesday pointed the finger at President Obama’s policies, naming in particular the 2009 stimulus (worth about $800 billion) and the health-care law, which has mostly not yet kicked in (and according to the Congressional Budget Office will not add to the deficit in its first 10 years).

The national debt is simply a matter of numbers, but the blame game is much more complicated. Let’s take a look.

The Facts

The Treasury Department’s “Debt to the Penny” Web site makes it easy to track the growth of the national debt during Obama’s presidency. There are two key figures — for publicly held debt and for gross debt, which includes bonds that the government owes to itself (such as Social Security trust fund bonds.)

As of Jan. 20, 2009, the publicly held debt was $6.31 trillion and the gross debt was $10.63 trillion. As of May 14, 2012, the publicly held debt was $10.92 trillion and the gross debt was $15.68 trillion.

So, the publicly held debt has grown by $4.61 trillion, and the gross debt has grown by $5.05 trillion. Thus it’s certainly correct that the national debt has grown by about $5 trillion under Obama.

Eric Fehrnstrom, a senior adviser to the Romney campaign, said that the $5 trillion figure came from these Treasury Department figures.

“We’re using the same standard that Obama used during his campaign in assigning blame to President Bush for the increase in debt that happened under his watch,” he said, pointing to a speech that then-Sen. Obama made during the 2008 presidential campaign.

“The problem is that the way Bush has done it over the last eight years is to take out a credit card from the Bank of China in the name of our children, driving up our national debt from $5 trillion for the first 42 presidents,” Obama said in Fargo, N.D. “Number 43 added $4 trillion by his lonesome, so that we now have over $9 trillion of debt that we are going to have to pay back — $30,000 for every man, woman and child. That’s irresponsible. It’s unpatriotic.”

Hmm, “unpatriotic” is certainly harsh. But, we’ve often said, two wrongs don’t make a right.

Romney also attributed the growth of the debt entirely to Obama’s policies. And, and while the numbers add up, that is a bit more difficult to justify.

First of all, Obama has failed to convince Congress to enact some of his proposed policies — such as higher taxes on the wealthy — that likely would have reduced the deficit and thus kept the debt growing more slowly.

But more to the point, a major factor in the debt explosion has been the decline in government revenues because of the recession. One could argue — and Romney might — that the laggard recovery is the result of Obama’s policies and thus he should also get all of the blame for the decline in revenues. But the chart below shows that the decline in revenues (the red line) began at start of the recession — a year before Obama took office.

The chart also shows an explosion of spending (blue line) began at the start of the recession — that is the result of automatic stabilizers such as unemployment insurance kicking in. The spending kept going up, and a good chunk of that is Obama’s responsibility. Still, as the chart shows, it is not such a simple answer to pin this all on Obama’s “policies.”

“While it’s true that revenue has decreased by a small amount, spending has soared — and it’s the role of a president to set a budget that ensures that spending stays in line with available revenue,” Fehrnstrom said. “President Obama has both increased non-defense discretionary spending and failed to propose any serious reforms to entitlement spending.” He noted that non-defense discretionary spending — annually appropriated by Congress — has increased significantly under Obama.

For readers wondering about the impact of the George W. Bush tax cuts on the national debt, the chart also shows slack revenue for a number of years after the recession at the start of Bush’s presidency, which is after the passage of the 2001 and 2003 tax cuts. There’s also a steady increase in spending under Bush.

While blame is often placed on the Bush tax cuts, the burst of spending under Bush is an often forgotten factor in the disappearance of the projected budget surplus. We have previously shown that this is how it breaks down from 2001 to 2011:

Increased spending (discretionary and mandatory): $4.3 trillion (36.5 percent)

Incorrect CBO estimates: $3.3 trillion (28 percent)

Tax cuts: $2.8 trillion (24 percent)

Higher interest costs: $1.4 trillion (12 percent)

The Pinocchio Test

Obama is the president, so he has ownership of the $5 trillion increase of the national debt during his years in office. He certainly tried to pin the increase of $4 trillion -- over eight years — on George W. Bush.

But that wasn’t quite right then, and it is equally simplistic for Romney to attribute all of this increase in the debt in the past three years to “Obama’s policies,” especially when he speaks of adding them up. We would have given Obama a Pinocchio back in 2008, and we are giving one to Romney now.

One Pinocchio

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