AMERICAN first ladies occupy an odd position, somewhere on the regal extremities of a presidential system that gives the country a cross between a chief executive in the Oval Office, and an elected monarch. A politician’s wife who is not a politician, expected to use the privilege of her position to advance only the most wholesome, patriotic causes (reading, childhood obesity, the welfare of military families), a first lady may still—with skill and guile—be used as an effective partisan weapon. At last week’s Republican convention in Tampa, Ann Romney performed useful service in vouching for the humanity, decency, trustworthiness and hard work of her husband Mitt. It was not ground-breaking oratory, but because the humanity of Mr Romney had been under attack from his opponents, the evident sincerity of her love for the Republican presidential candidate had some power. On Tuesday night in Charlotte, as the Democrats opened their convention, Michelle Obama delivered a much more obviously political speech that did several different things. Firstly, it sought to harness the advantage of incumbency to defend Mr Obama’s patriotism, that of his administration and (more quietly) that of his allies in the broader Democratic movement. In her most queenly manner, the first lady talked of the privilege and honour of meeting military families, brave civilians and “wounded warriors” as a presidential consort—playing up Mr Obama’s record as a war president who brought troops home from Iraq and who killed Osama bin Laden. Matching praise for “teachers in a near-bankrupt school district who vowed to keep teaching without pay” was more of a present for the Democratic base, in which teachers and members of public-sector unions angry at spending cuts loom large. These sections were fine, but nothing special.

Secondly, she delivered a series of nakedly partisan swipes at the privileged background and competence of Mr Romney, her husband’s challenger, and these bits were not very good. Thus she stressed, clunkingly, how she and her husband were “both raised by families who didn’t have much in the way of money or material possessions”, but made up for it with love, self-sacrifice and ambition for their children—unlike (we were supposed to conclude) Mr Romney, the son of a wealthy executive turned politician. She also talked of how presidents constantly take hard decisions “where no amount of data or numbers will get you to the right answer”. That was a nod to those asking whether Mitt Romney’s success as a private-equity boss, which saw him patiently sift and weigh screeds of data and financial information to identify low-risk, high-return investments, gave him the right sort of executive experience, given the rapid-fire, high-stakes nature of Oval Office decision-making.

There was lots of stuff about what a sweet, loving and admirable husband and father Mr Obama is, which frankly did not advance the cause of human understanding very much: the Democrats in the crowd lapped it up, while those watching at home who dislike the current president will not have had their minds changed.

But in other passages, the first lady’s speech did one last thing: it mounted a rebuttal of the core argument advanced at the Republican convention about the individualistic nature of American success, and how it is government’s first job to get out of the way of wealth creators, rather than smothering them with regulations or cosseting and unmanning citizens with un-American levels of welfare. Those bits of Mrs Obama’s speech were more clever, and interesting.

Mrs Obama did not mount a straightforward defence of the public sector or government intervention—indeed, she did not need to, as half the speakers on Tuesday spent their time defending the public sector and praising government spending, or investment, as they called it. Instead, she set out to chip away at that Republican praise for success, and to imply that it ungratefully claims too much personal credit for things that go right.

Now this is, of course, dangerous territory for the Obamas. The president is still being whacked with attack ads over his garbled "you didn't build that" remarks. Though he was talking about the importance of good schools, roads and other public infrastructure, the Republicans used the line as a central rallying cry at their convention. Speaker after speaker expressed resentment over the idea that their own hard work was not integral to their success. “You did built that”, they told the crowd in Tampa, while assuring them that Barack Obama both hated success and was bent on turning America into a “nightmare of dependency” (as Rick Santorum put it).

In Charlotte on Tuesday Mrs Obama suggested that this was slightly bad manners, not to mention arrogant. She described how her father had “hardly ever missed a day of work” despite suffering from multiple sclerosis, and how he had saved and scrimped to pay the “tiny portion” of his children’s college tuition that was not covered by grants and student loans, because paying for his children’s education was “what it meant to be a man”. She talked of Barack Obama’s grandmother, who spent years working tirelessly in a community bank without complaining when less able male colleagues were promoted above her. The rebuke to Republicans was there to be heard: this was Mrs Obama praising the dignity of the loyal employee, and arguing that the poor (or less than wealthy) can be just as deserving as employers and bosses.

The first lady also rebutted the charge that she and her husband dislike private-sector success, adding her own moral twist. She revisited her husband’s “you didn’t build that” remarks and tried to make them into a broader moral argument about gratitude.

Like so many American families, our families weren’t asking for much. They didn’t begrudge anyone else’s success or care that others had much more than they did...in fact, they admired it. They simply believed in that fundamental American promise that, even if you don’t start out with much, if you work hard and do what you’re supposed to do, then you should be able to build a decent life for yourself and an even better life for your kids and grandkids. That’s how they raised us…that’s what we learned from their example. We learned about dignity and decency—that how hard you work matters more than how much you make…that helping others means more than just getting ahead yourself. We learned about honesty and integrity—that the truth matters…that you don’t take shortcuts or play by your own set of rules…and success doesn’t count unless you earn it fair and square. We learned about gratitude and humility—that so many people had a hand in our success, from the teachers who inspired us to the janitors who kept our school clean…and we were taught to value everyone’s contribution and treat everyone with respect. Those are the values Barack and I—and so many of you—are trying to pass on to our own children. That’s who we are.

Some will find that an unconvincing line of attack. It is arguable that even if Mr Obama garbled his remarks about the role played by government infrastructure, he does have a poor relationship with many business leaders, four years into his presidency.

But I thought the line about “gratitude and humility” was clever, because in their worst moments in Tampa the Republicans did sound shrill and self-congratulatory, not to mention hypocritical (this reporter’s favourite moment involved a testimonial on stage from a Hispanic businessman whose main gripe, it turned out, was that his firm had not secured fat enough contracts from the government).

The first lady’s communitarian counter-blast had one last interesting aspect. Like many speakers on this first evening in Charlotte, she sought to cast her message of community support and mutual solidarity as rooted in the country’s most ancient traditions.

There was almost a sense of poker at work. In Tampa, Republicans talked a lot about their parents, the second world war and the "greatest generation", and the founding fathers. On the first night in Charlotte, speaker after speaker spoke about their grandparents (ie, I’ll see your mother, and raise you my granny).

From Democratic governors, senators and mayors speaking in Charlotte there was talk of pioneers heading west in wagon trains and of George Washington fighting the British redcoats. Mrs Obama traced her community-based version of the American dream back to the American revolution, in which patriotic farmers and blacksmiths came together to “win independence from an empire”.

In short, the Democrats are on offence against what they clearly think was a purely individualistic narrative of success from the Republicans in Tampa last week. And while never quite mentioning Mitt Romney by name, the first lady was a key player in that offensive strategy. Politics by another means. It certainly fired up the hall, who gave her repeated standing ovations. Whether it impresses swing voters in the country remains to be seen.

(Photo credit: AFP)