The story of the political career of Kamala Harris can be told, in part, by videotape. Ms. Harris has risen to public attention — and more important, risen to the attention of Joseph R. Biden Jr., who picked her as his running mate on Tuesday — because of a series of often dramatic moments during congressional hearings, town halls and primary debates. Here are five of them, with our commentary.“That Little Girl Was Me”Adam: This was in many ways the pivotal moment of Ms. Harris’s presidential campaign — “that little girl was me” — and it shows why Mike Pence is probably worried about facing her in a vice-presidential debate. She is incredibly sharp and piercing. Her challenge to Joe Biden over his opposition to busing during the June 27, 2019, primary debate shows her training as a prosecutor. It’s one of those attacks that you don’t see coming until it’s too late (though I’m not sure there was much Mr. Biden could have done in response. He was left, as you probably recall, struggling). What I found striking about this is that even though we can assume it was a prepared attack, it didn’t feel canned, as so many debate lines do. (Go and Google “Klobuchar-Debate-Jokes.”)Shane: It didn’t, and that has been one of Ms. Harris’s great strengths on the debate stage, in Congress and even while giving speeches: sounding authentic and of the moment, even when her remarks are deeply prepared. Prosecutors, after all, carefully craft and memorize their arguments. The corollary is that she is often less forceful and formidable off-the-cuff.Adam: You make a good point about her training in Congress. You could see that. She doesn’t lapse into mind-numbing Congress-speak, right? (Please say yes.)Shane: Yes — I mean, people forget, with the speed of news cycles these days, but she hasn’t been in D.C. that long! Her opening line in the debate sequence was just devastating. One of the more cutting “but”s in the English language is the one that comes after “I do not believe you are a racist.”Adam: And the split-screen didn’t help; everyone was watching Mr. Biden. But I have a question for you: If it showed her as such a good debater, why did her campaign collapse? Did she come across as insincere or as the calculating politician to regular people who don’t make a profession out of watching debates?Shane: Oh, go for the simple questions, Adam.Adam: Hey, that’s my reward for going first! Take it up with the editors.Shane: The shortest version is that for all of the peaks she generated — her big announcement rally, the debate moment — Ms. Harris did not find a sustainable lane in a primary where Mr. Biden occupied the political center and Bernie Sanders and Elizabeth Warren locked down the left. Oh, her campaign was troubled by intense infighting and she ran out of cash. Also: She dropped out early, when she could have limped along longer. Her vice-presidential selection shows why: Exiting gracefully gave her a bump that stumbling out of Iowa in fourth place would not have.Adam: If Ms. Harris’s challenge to Mr. Biden on school busing was a high point in her campaign, could these moments from 2019, about Ms. Harris’s view on health care policy, have been a low point?Shane: Hmm, I don’t think these were exactly a low point. But I do think they revealed one of her candidacy’s greatest shortcomings: It wasn’t clear where she stood on health care, one of the most fundamental issues of the cycle. And interestingly, her campaign had to perform some cleanup after both of these moments — downplaying her suggestion that you could just get rid of private insurance in January and then, in June, saying she had misheard the question at the debate.Adam: I suspect we are going to see the raise-your-hand clip quite a bit over the next three months. As you noted, she said that she misheard the question, and thought she was being asked if she would give up her private insurance. I’m not sure that anyone else on the stage heard it that way, but granting that: Her initial tentativeness has a “no, you go first” feeling to it, which could play into criticisms of her that she is cautious and holds her finger in the wind. And it sure plays into the effort by the Trump camp to paint her as liberal.Shane: Well, here’s the irony: I think these exchanges, and the fact that she later backtracked from them, show how she was not, in fact, stridently liberal on this issue. Still, if Democrats have already rewatched the Biden debate moment and dreamed about her filleting Mr. Pence, the Trump campaign has to be just as happy with the Tapper clip. It is already using it as a cudgel to hammer their message of Ms. Harris as a radical.Adam: Exactly. Next!“Yes or no please, Sir.”Shane: This was another instance of Ms. Harris flashing her prosecutorial experience: She stumped Attorney General William Barr, who was testifying before the Senate Judiciary Committee in May 2019, from the very first question. It was very specifically worded to be very broad: “Has the president or anyone at the White House ever asked or suggested that you open an investigation of anyone?” In other words, had anyone ever suggested an investigation into anyone. Mr. Barr sputtered and stalled. “It seems you’d remember something like that,” she followed with the dagger.Adam: This was better than Perry Mason. I mean the new one.Shane: So why is she the vice-presidential nominee instead of the presidential one? I don’t think there is an equivalent clip of Joe Biden in 2019.Adam: Or in any year. That goes back to our earlier discussions. She has had good moments — and not so good moments — as a candidate. When she’s in her comfort zone, the prosecutor confronting a tough witness, she is very powerful. When she is on a debate stage talking about health care or an issue that has confounded the party, perhaps not so much (and in that, she’s like many first-time presidential candidates). But whatever your politics, this exchange — “Yes or no please, sir” — is pretty arresting television.Shane: This wasn’t a one-time thing with a sitting attorney general. Back at the start of the Trump administration, she questioned Jeff Sessions so forcefully he interrupted to say, “It makes me nervous.”Adam: I bet even President Trump was applauding that Harris-Sessions exchange.Tussling with Tulsi GabbardShane: Representative Tulsi Gabbard had made it clear ahead of this July 2019 debate that she planned to attack Ms. Harris, but the laundry list of accusations she unloaded was still jarring — everything from prison labor to marijuana to the death penalty. And Ms. Harris basically didn’t respond to the specifics. What impact did that have?Adam: Ms. Gabbard raised many of the criminal justice issues that have given many on the left wing of the party pause about the senator from California. Her answers there seemed — well, not quite ready for prime time. Presumably her answers would have gotten sharper if she had stayed in the race. But considering the reaction to her selection so far, it doesn’t seem to have hurt her. I’m guessing that this is not a line of attack that the former governor of Indiana is going to be inclined to use at the vice-presidential debate.Shane: You never know! The Trump campaign has tried to attack Mr. Biden both for locking up people of color with the 1994 crime bill, and supporting the defunding of police now (which Mr. Biden does not).Adam: Well, this one is a little-bit of a head-scratcher. For almost seven minutes — including the time when they stopped the clock because of protests in the audience and points of order from panel members — Ms. Harris kept pushing Brett Kavanaugh, appearing at his U.S. Supreme Court confirmation hearings in September 2018, about whether he had ever spoken to anyone at the law firm founded by President Trump’s personal lawyer about the Robert Mueller case. “Be sure about your answer sir,” she said, as Mr. Kavanaugh looked perplexed. “I’m asking you a very direct question. Yes or no.”Shane: It was very dramatic.Adam: Though ultimately unresolved. Mr. Kavanaugh never did answer the question, saying he did not know everyone at the law firm so he could not say. From watching this, it sure seemed as if Ms. Harris had something in mind. (You know that adage about attorneys, right: Never ask a witness a question that you don’t know the answer to.) But if she had someone in mind, she never mentioned the name during the hearing. Did it ever come out? Was there a there there?Shane: The short version is no. Mr. Kavanaugh later would say he didn’t speak to anyone at the firm. Ms. Harris would tell reporters, “I have good reason to believe there was a conversation.”The loudest grumbles about her Kavanaugh grilling came from Republicans who accused her of dirtying him with innuendo. But now Mr. Kavanaugh is on the Supreme Court and Ms. Harris is the Democratic nominee for vice president.