Romney gave McCain a huge opening last night, and it’ll be interesting to see if he takes it. In Romney’s post-primary speech, during his usual three-pronged pander (family! military! economy!), he described his business know-how this way: “I spent my entire life in the real economy. I know why jobs come; I know why they go.”

Now here’s how McCain’s speechwriters can use this during tonight’s debate: McCain says, “Governor Romney says his past as a businessman gives him an insight into his economy. Just last night, in fact, he said during a speech, ‘I spent my entire life in the real economy. I know why jobs come; I know why they go.’ And he’s right—because as the hatchet-man for Bain Capital, when he came in and slashed companies for profit, he forced thousands of good Americans out of their jobs. He knows exactly how jobs go, because they go through him.”

This is low-hanging fruit, McCain. You know it.