One message loud and clear from this Charlotte convention: the Democrats have a very clear theory of their vulnerabilities and opportunities.

There was Elaine Brye, a white blond mother of four service personnel (and a fifth perhaps soon to enlist), to speak immediately before Michelle Obama about the first lady's devotion to the care of military families like her own.

Massachusetts Governor Deval Patrick won his loudest applause by reminding delegates of the president's order to kill Osama bin Laden.

Speech after speech praised entrepreneurs and small business, with the first lady herself stressing how much she admired the economically successful - even as she vividly depicted her own economically humble origins.

God may not have made it into the Democratic platform, but He opened and closed keynote speaker Julian Castro's speech.

Those softer messages dominated the 10-11 ET hour, when the networks rolled.The Democrats reserved their fiercest attacks for the cables, watched by the more intense partisans.

They revived Ted Kennedy from the dead to deliver stinging personal attacks on Mitt Romney. (Has any convention ever done anything like that before?)

Ohio Governor Ted Strickland delivered union-hall style economic xenophobia, accusing Romney of a lack of "economic patriotism" because he had investments abroad. (What do Austan Goolsbee, Larry Summers, Laura D'Andrea Tyson, Gene Sperling, and Paul Volcker think of that level of economic analysis?)

Julian Castro's speech signally failed to launch the Castro 2020 bandwagon, but it scathingly linked Romney's supposed social exclusiveness to Paul Ryan's bold policy adventure.

Mitt Romney, quite simply, doesn’t get it. A few months ago he visited a university in Ohio and gave the students there a little entrepreneurial advice. “Start a business,” he said. But how? “Borrow money if you have to from your parents,” he told them. Gee, why didn’t I think of that? Some people are lucky enough to borrow money from their parents, but that shouldn’t determine whether you can pursue your dreams. I don’t think Governor Romney meant any harm. I think he’s a good guy. He just has no idea how good he’s had it.

We know that in our free market economy some will prosper more than others. What we don’t accept is the idea that some folks won’t even get a chance. And the thing is, Mitt Romney and the Republican Party are perfectly comfortable with that America. In fact, that’s exactly what they’re promising us.

Sword and shield. The Democrats have their plan.