From the moment Michelle Obama strode onstage at the Democratic National Convention on Tuesday night baring arms, her appearance and her words were a reminder of why she had been such a powerful communicator as a first lady — and as a writer and speaker thereafter.

As she wrote in her memoir, “Becoming,” she came to understand that if the spotlight was going to be thrust upon her, she might as well use every photon available to her own ends — including those focused on what she wore. It is, after all, part of showing up.

So as she spoke in support of Vice President Kamala Harris, as she spoke of her mother as well as all mothers, of morality and decency (and lies and racism), she did so in a pantsuit — but not one that looked much like the traditional political woman’s pantsuit.

Rather she wore one that took the pantsuit forward, that took it to the next stage. Sound thematically familiar?

To be specific, she wore a dark navy sleeveless jacket belted over cropped trousers. The lapels of the top were de- and reconstructed to cross over the throat in an almost militaristic way, and the shoulders jutted out to frame the biceps. It was both understated and edgy, kind of armorial. This was going to be a fight, her tunic and her speech suggested, and everyone should gear themselves up to get out the vote.