Health and Human Services Secretary Robert F. Kennedy Jr. has put Sen. Bill Cassidy (R-La.) in a political bind, squeezed by his loyalty to President Trump and commitment to medicine.
Cassidy, the chair of the Senate Health, Education, Labor and Pensions (HELP) Committee, publicly wavered over Kennedy’s confirmation, sharply criticizing his views before eventually voting for him.
Cassidy said he secured a series of promises about vaccine safety, including for Kennedy to not undercut public confidence in vaccines.
“If Mr. Kennedy is confirmed, I will use my authority … to rebuff any attempts to remove the public’s access to lifesaving vaccines without ironclad, causational scientific evidence that can be defended before the mainstream scientific community and before Congress,” Cassidy said on the Senate floor in February, just after he voted to advance Kennedy’s nomination out of committee.
Cassidy said Kennedy also pledged to keep in place a pivotal independent advisory panel on vaccine policy.
“If confirmed, [Kennedy] will maintain the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) without changes,” Cassidy said.
On Monday, Kennedy fired the entire 17-member panel, arguing a “clean sweep” was needed to purge conflicts of interest and help restore trust in vaccinations and public health.
The move was an unprecedented escalation in Kennedy’s quest to reshape the nation’s vaccine policy and seemingly ignored one of the key promises Cassidy said he extracted from the longtime anti-vaccine activist.
However, the second-term Louisiana senator and medical doctor did not publicly confront the Kennedy this week, pointing to his political vulnerabilities as he runs for reelection in 2026 and hopes to survive the deep red state’s GOP primary.
Robert Hogan, department chair and political science professor at Louisiana State University, said it seems clear that Kennedy is playing Cassidy for a fool — but that won’t matter to GOP primary voters.
“You would think that that would hurt him electorally, but … I think ultimately, what could have hurt him is if he had stuck with his professional standards and the standards of the medical community” and spoken out against Kennedy, Hogan said.
“Keep in mind that in Louisiana, just a few days ago voted to make ivermectin available without a prescription. … Republicans are all in on this kind of thing and in that kind of environment, especially in a nomination battle where they are going to be the vast majority of people voting … it doesn’t pay at all to push Kennedy on these matters,” Hogan said.
Cassidy spent three decades as a practicing gastroenterologist before being elected to the House in 2009 and the Senate six years later. He won his 2020 election in a landslide, but he committed a cardinal sin in today’s Republican party when, in 2021, he voted to convict Trump of impeachment for trying to incite a riot at the Capitol on Jan. 6.
After his vote against Trump, state Republicans changed the rules to create a closed primary, where only Republicans and people who aren’t registered in any other party can vote.
Since Trump’s reelection, Cassidy has tried to make amends. He’s supported every controversial Cabinet nominee and touted his visits to the White House to brief Trump.
Cassidy reported raising $1.36 million during the first quarter of 2025 with $7.5 million cash on hand. His campaign said it was the most ever by an incumbent Louisiana senator at this early stage in the campaign.
Trump has so far largely stayed quiet on the race, but The Associated Press reported last month that Trump and Louisiana Gov. Jeff Landry (R) have discussed having the president support Rep. Julia Letlow (R) as a primary challenger to Cassidy.
State Treasurer John Fleming (R), a former House member who is also a medical doctor, has already launched his primary campaign against Cassidy.
Hogan said Fleming is a formidable opponent.
“If it comes down to, they’re equal on every other dimension except [Fleming] did not vote to impeach Trump? That’s the message, I think that will come through very clear to Republican voters,” Hogan said.
Cassidy declined to comment for this article. He hasn’t said much about Kennedy’s latest move, telling reporters only that he is having conversations with the secretary. He also wouldn’t say if Kennedy violated their agreement and instead pointed to a social media post.
“Of course, now the fear is that the ACIP will be filled up with people who know nothing about vaccines except suspicion,” Cassidy wrote on the social platform X. “I’ve just spoken with Secretary Kennedy, and I’ll continue to talk with him to ensure this is not the case.”
Firing ACIP members is far from the first time Kennedy has flouted Cassidy’s guardrails.
Earlier this month, Kennedy bypassed ACIP entirely when he declared pregnant women and healthy children don’t need COVID-19 vaccines.
He canceled hundreds of millions of dollars in mRNA vaccine contracts and forced out the head of the Food and Drug Administration’s vaccines division.
As part of his commitment to Cassidy, Kennedy agreed to testify upon request on a quarterly basis. Yet he declined to do so when Cassidy requested a hearing in April following massive layoffs at HHS.
Instead, he testified weeks later during a budget hearing on the HHS appropriations request. Cassidy pointed out it was the first time “in at least two decades” an HHS secretary testified to the HELP Committee about a budget request.
Before the start of the hearing, Cassidy gave Kennedy a clear sign of support when he walked to the front of the hearing room and shook Kennedy’s hand in front of a barrage of cameras.
While Cassidy largely avoided the issue of vaccines during the hearing, Democrats did not.
Sen. Chris Murphy (D-Conn.) accused Kennedy of misleading senators and the public about his support for vaccines.
“If I were the chairman, who believes in vaccines and voted for you because he believed what you said about supporting vaccines, my head would be exploding,” Murphy said.
