( CNN ) -- After Michelle Obama 's speech Tuesday night , it will be very difficult for her critics to portray her as angry or aggrieved . She rarely raised her voice . She smiled , she charmed , she seemed to tear up . She said not an unkind thing about her political opponents . Indeed , she never mentioned them . Yet she eviscerated Mitt Romney and everything he represents by stunning contrast , by recounting her modest upbringing and reminding her audience that President Obama shared her unassuming roots . It was a bravura political performance cloaked in an apolitical narrative . After Tuesday night , it will be very difficult for the Rush Limbaugh League to accuse the first lady of being unpatriotic , of failing to sufficiently love America . From her introduction by one of the nation 's military supermoms -- Elaine Brye , mother of four military officers -- Obama spoke of schoolteachers , of firefighters , of wounded warriors and their sacrifices . Given Romney 's failure in his convention speech to even acknowledge men and women in uniform , Obama 's salute to them was another striking contrast , served up without venom or bile . From their first presidential campaign , Michelle Obama 's role has been at least as difficult to navigate as her husband 's . As the first black woman to represent the country in a job with few defined duties but generations of cherished symbolism , she has had to endure relentless vicious attacks . She has been caricatured , as she has noted , as an `` angry black woman . '' She has been cast as hostile to whites . And her campaign against childhood obesity has earned cruel denunciations from the right , including a remark from an overweight GOP lawmaker that she has a `` large posterior . '' She has had to suffer through that privately , never shedding her calm exterior in public . She has had to shield her children from scrutiny and attempt to ensure they enjoy something close to normality . And she has had to carve out an official portfolio of suitable causes . But she has done all that with aplomb , racking up an enviable approval rating . If she was once a reluctant political wife , she seemed Tuesday night to have found a way to enjoy her role . She was relaxed and confident . She was warm and approachable . ( She was also lovely . That should n't matter , but it does . Just ask any woman in the national political spotlight . ) Opinion : Will Michelle Obama 's speech change history ? She wove a narrative thread around her insecurities about how the pressures of life in the White House might change her husband and her family . And she delivered a resounding assurance that the president remains not only loving and compassionate but also grounded in honesty and integrity . He can make the tough calls . `` Well , today , after so many struggles and triumphs and moments that have tested my husband in ways I never could have imagined , I have seen firsthand that being president does n't change who you are -- it reveals who you are . '' In a speech full of great lines , that was my favorite . If Romney is a congenital flip-flopper whose views shift with the political winds , Obama 's character has already been revealed , she noted without rancor or even explicit comparison . `` And I 've seen how the issues that come across a president 's desk are always the hard ones -- the problems where no amount of data or numbers will get you to the right answer ... the judgment calls where the stakes are so high , and there is no margin for error , '' she said . Rarely have I heard a political speech that so deftly hit all the right notes and so stirringly found all the right chords . Opinion : Michelle Obama has redefined black women . She deftly deflected Republican accusations of class envy : . `` Our families were n't asking for much . They did n't begrudge anyone else 's success or care that others had much more than they did . ... In fact , they admired it . '' But she also noted that Democrats do n't believe in Ayn Rand 's hyperindividualism . `` 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 . '' This was red meat served up in a bed of lovely salad greens from Obama 's garden . Who could argue that was n't a fitting entree from a First Lady ? The opinions expressed in this commentary are solely those of Cynthia Tucker .
Cynthia Tucker : It would be tough for critics to paint Michelle Obama as angry , aggrieved . She says Obama 's DNC speech was not unkind , yet eviscerated Mitt Romney candidacy . Tucker : Obama saluted military , told of humble roots , shared concerns with other Americans . She made case for her husband , drew contrasts with Romney without venom , Tucker says .