Vice President Kamala Harris' stumbles during her first foreign trip have rekindled the debate from her presidential campaign about whether she — and not her staff — is to blame, Axios' Sarah Mucha reports.

Why it matters: While Harris' only overture toward running for president in 2024 has been a trip to New Hampshire in April, the vice president is in a prime position to cast herself as the best choice for Democrats should President Biden not seek a second term.

• Such international trips and her leadership of the migration and jobs portfolios given to her by Biden will let her showcase herself for the No. 1 slot in a future election.
• The White House didn't offer comment but aides noted that Harris has done numerous interviews without problems and the exchange during her trip last week came after repeated questions on the same topic.

Between the lines: One factor that led Harris to become the first major Democrat to exit the 2020 race — despite a massive announcement rally — was that she surrounded herself with a staff that didn't always serve her well.

• Now, as vice president, she has the latitude and stature to tap some of the country’s best talent to work on her team.
• Her trip to Guatemala and Mexico still garnered a flurry of negative headlines.
• Most prominently, Harris stumbled on an easily anticipated question about the border during an interview with NBC News anchor Lester Holt, growing defensive. Even follow-ups with other reporters didn't go much better.

The intrigue: The vice president can be notoriously difficult to prep, multiple former aides told Axios.

• Harris is “intensely intellectually curious,” as one former aide put it, which often sends briefings into a “rabbit hole” on topics that may not necessarily be relevant to the appearance or interview at hand.
• “If somebody doesn’t knock it out of the park their first time, then they will always have a tough time,” said one former aide.
• Each spoke to Axios on the condition of anonymity to comment freely.

But, but, but: Harris was under an enormous amount of pressure on this trip. Not only was it her first visit abroad, but she is also the first female vice president and the first woman of color to be a heartbeat away from the presidency.

• And because she is seen as Biden’s natural successor, Republicans have eagerly capitalized on any misstep for their own political gain.

Between the lines: Harris also is in a tough spot managing two issues — immigration and voting rights, the latter of which she’s reported to have chosen herself — that have little upside and huge downside.

🎧 Listen: Dan Primack of the Axios Re:Cap podcast interviews senior White House official Juan Gonzalez about the trip.

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If a bipartisan group of lawmakers fails to strike a deal on the infrastructure proposal it's negotiating with the White House, ramming through a package using the partisan reconciliation process isn't a guaranteed solution, Axios' Neal Rothschild and Alayna Treene write.

Why it matters: Getting 51 Democratic votes would be a long, uphill battle. And moderates within the party are balking at the cost of President Biden's spending — even as progressives openly lament that the "transformational" change they seek is slipping out of reach.

• "An infrastructure package that goes light on climate and clean energy should not count on every Democratic vote," Sen. Martin Heinrich (D-N.M.) tweeted Wednesday.

Driving the news: Sens. Joe Manchin (D-W.Va.) and Kyrsten Sinema (D-Ariz.) have taken most of the heat for opposing parts of Biden's bill, but several other Democrats also are wary of certain provisions — most notably its steep, nearly $4 trillion price tag.

• Sen. Jon Tester (D-Mont.) told Axios he hasn't decided on his "upper limit" on spending but said, "There's definitely room for negotiation."
• “I think it's high,” Sen. Angus King (I-Maine) told Axios. “But I'm not prepared to say where I want to change it.”
• "The price tag is very negotiable. We'll see what we do bipartisan and then we can adjust the price," Sen. Tim Kaine (D-Va.) said.

The intrigue: An intra-party dispute would create a whole new host of problems for Biden.

• Rather than blaming Republicans if a package collapses, he'd be forced to haggle with members of his own party and accept some blame if they don't come on board.
• Already, some Democratic senators are venting in the open.
• Their vision of remaking America with a once-in-a-generation infrastructure, climate and social services package is colliding with the cold, hard reality of a razor-thin Senate majority and the divisions within their own party.

What they're saying: "Just a gentle, friendly reminder that the executive branch doesn't write the bills," Sen. Brian Schatz (D-Hawaii) tweeted.

• Sen. Sheldon Whitehouse (D-R.I.) also sounded the alarm last week: "I’m now officially very anxious about climate legislation."

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A national police union is spending hundreds of thousands of dollars attacking The Squad, records reviewed by Axios' Lachlan Markay show.

Why it matters: The $510,000 in spending by two PACs associated with the International Union of Police Associations is the largest independent political expenditure of the 2022 cycle to date. It appears geared less toward unseating any of the members and more toward raising money for the groups themselves.

What's happening: Both groups — Law Enforcement for a Safer America PAC and Honoring American Law Enforcement PAC — are affiliated with the International Union of Police Associations.

• The Florida-based IUPA represents about 20,000 law enforcement professionals.
• Together, the two PACs reported spending $127,500 attacking each of the four House Democrats in the progressive "Squad": Reps. Alexandria Ocasio Cortez of New York, Ilhan Omar of Minnesota, Ayanna Pressley of Massachusetts and Rashida Tlaib of Michigan.
• That's more than any independent political group has reported, so far, on a single independent expenditure in a 2022 midterm race.
• The actual content of the text messages was not immediately clear. Neither PAC responded to requests from Axios for comment.

Between the lines: None of the four members the PACs are targeting is particularly vulnerable, suggesting the goal of the expenditures is, at least, partly to raise more money for the PACs themselves.

• The two PACs spent nearly $18 million during the 2020 cycle. But the vast majority went toward fundraising. They spent just over 5% on political activity, much of which appears to have also asked for additional donations.
• The IUPA union also spends the vast majority of its money on fundraising, with very little going toward grants or union representation and organizing.
• The union and its PACs have been scrutinized over allegedly misleading fundraising practices, frequently involving telemarketing calls.

The big picture: Ocasio-Cortez, Omar, Pressley and Tlaib are lightning rods for conservatives — and potent fundraising draws as a result.

• Policing and public safety are at the forefront of the conservative political consciousness.
• That can be lucrative for groups looking to rake in small-dollar donations from contributors not suspecting their money will be used largely to perpetuate an organization — rather than finance attacks or candidates against its opponents.

The head of the International Atomic Energy Agency tells Margaret Talev for "Axios on HBO" that it's "essential" to have a nuclear deal with Iran because otherwise "we are flying blind."

Driving the news: Director-General Rafael Mariano Grossi spoke at IAEA headquarters in Vienna, ahead of Iran's June 18 presidential election and a June 24 extension on negotiations seeking to restore curtailed surveillance of Iranian nuclear sites and salvage the 2015 deal.

• The Biden administration wants to re-enter the deal but impose new restrictions. Iran, which has long insisted its nuclear program is peaceful, wants sanctions lifted without opening itself to broader limitations.

Flashback: Former President Trump pulled the U.S. out of the deal in 2018. Iran has since disclosed enriching uranium at levels that far exceed the deal's limits but technically fall below the 90% considered weapons-grade purity.

What they're saying: Asked whether he believes Iran has an active nuclear weapons program, Grossi responded: "No, there is no information indicating that at the moment."

• But he raised concerns about Iran's stepped-up enrichment combined with the international community's reduced visibility in recent months.
• "This is very serious," Grossi said. "When you enrich at 60%, you are very close. It's technically indistinguishable from weapon-grade material. So when you combine this with the fact that our inspection access is being curtailed, then I start to worry."

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President Biden and first lady Jill Biden called on Queen Elizabeth II at Windsor Castle.