Part III, which summarise his argument, and looks specifically at the debt he inherited, is here. Interestingly, it's full of graphs and figures, some from what people would say are "suspect" sites (such as Think Progress), but also the Cato Institute (!) and the Ludwig von Mises Institute (!!).
Johnson, now loathed by the Right for his abandonment of them, seems to me to make a pretty good looking case.
Googling around, I also found this column by Ezra Klein in February this year, looking at the question of the Obama deficits. He starts:
When Obama took office, the national debt was about $10.5 trillion. Today, it’s about $15.2 trillion. Simple subtraction gets you the answer preferred by most of Obama’s opponents: $4.7 trillion.It turns out to be a bit of a complicated question as to who to assign responsibility to for various things that affect the deficit, but the conclusion he reaches is this (my bold):
But ask yourself: Which of Obama’s policies added $4.7 trillion to the debt? The stimulus? That was just a bit more than $800 billion. TARP? That passed under George W. Bush, and most of it has been repaid.
There is a way to tally the effects Obama has had on the deficit. Look at every piece of legislation he has signed into law. Every time Congress passes a bill, either the Congressional Budget Office or the Joint Committee on Taxation estimates the effect it will have on the budget over the next 10 years. And then they continue to estimate changes to those bills. If you know how to read their numbers, you can come up with an estimate that zeros in on the laws Obama has had a hand in.
In total, the policies Obama has signed into law can be expected to add almost a trillion dollars to deficits. But behind that total are policies that point in very different directions. The stimulus, for instance, cost more than $800 billion. So did the 2010 tax deal, which included more than $600 billion to extend the Bush tax cuts for two years, and hundreds of billions more in unemployment insurance and the payroll tax cut. Obama’s first budget increased domestic discretionary spending by quite a bit, but more recent legislation has cut it substantially. On the other hand, the Budget Control Act — the legislation that resolved August’s debt-ceiling standoff — saves more than $1 trillion. And the health-care reform law saves more than $100 billion.My feeling that Obama has been relatively competent, as far as Presidents go, seems better justified than I realised.
For comparison’s sake, using the same method, beginning in 2001 and ending in 2009, George W. Bush added more than $5 trillion to the deficit.