Mitt Romney today made a surprise campaign appearance at Solyndra, the solar-panel company that filed for bankruptcy after receiving half a billion dollars in federal loan guarantees. Originally part of Romney’s comeback to the Bain charges, it has emerged as a central part of his critique of Barack Obama’s economic policy.

“It’s a symbol not of success but of failure,” Romney said at the event. “I’m afraid the reason that the stimulus has been unsuccessful, that the turnaround has taken so long to occur, that the recovery has been tepid, is that the president fails to understand the basic nature of free enterprise in America.”

Romney even hit Obama on crony capitalism:

I also note how damaging a decision like this is for free enterprise generally. What you’re saying to other inventors, to other entrepreneurs, particularly in the solar space, is that the best way to get ahead is not with the best ideas and the best technology and the best people and the best marketing, but instead with the best lobbyists. That is not the nature of how America works.

I wrote about how Solyndra was representative of the Obama administration’s broader approach to economics in the print edition. Recent national and swing state polls have shown Romney pulling even with Obama.