If Solyndra was a mistake, it was, as my friend Joe Nocera made clear in a recent New York Times column, an understandable one. But it also illustrates Obama’s greatest weakness as he began his presidency: the lack of understanding of the executive branch that, for example, led him to leave spending too much of the stimulus money to the Department of Energy. As this column noted in 2009, the DOE has a terrible record when it comes to effective spending. Indeed, as of mid-September of this year the DOE had “only two weeks left [in the fiscal year] to commit the [stimulus loan] program’s remaining $9.3 billion,” according to the Washington Post‘s Joe Stephens and Carol Leonnig. Obama has since acknowledged his early innocence about whether a project was truly “shovel ready” or not, so I am hopeful that he will do better in the future. I am fortified in this view by his appointment of Jack Lew to succeed Peter Orszag as head of the Office of Management and Budget. Lew, as a knowledgeable OMB veteran, understands the bureaucracy much better than his predecessor.