President Donald Trump appears determined to please some of the worst elements of his MAGA base as he "tramples his own legacy," according to Michael Steele, a former chairman of the Republican National Committee and the first Black American to hold the post, who argues in a new MS NOW opinion piece that the president is mounting a "desperate pitch" as his pool of backers grows shallower.

Steele, who led the Republican National Committee from 2009 to 2011 and has since become an outspoken conservative critic of Trump and his political agenda — including in his role as a political analyst for MS NOW — wrote in the piece published Sunday that the president is now "undermining [the] biggest accomplishment" of his first term in a bid to attract "conspiracy-minded voters."

At issue is Trump's recent executive order calling for major changes to the childhood vaccination schedule, issued after years of right-wing conspiracy theorists falsely claiming that vaccines are dangerous, especially to children. The order specifically calls for the measles, mumps and rubella shots — commonly and safely administered as a combined injection — to be spaced out across multiple appointments. The combined MMR shot has been in use since it was licensed in 1971, and the childhood immunization schedule is set by the CDC's Advisory Committee on Immunization Practices, whose recommendations most states use to determine school-entry vaccination requirements. Measles was declared eliminated in the United States in 2000, and health officials have tied its return in recent years — including a 2025 resurgence that was the country's largest in decades — to communities with low vaccination coverage.

Steele wrote that the order marked "a remarkable reversal for a president who once treated vaccine development as one of the signature achievements of his first term."

"President Donald Trump's handling of the COVID-19 pandemic was riddled with misinformation and chaos," Steele wrote. "But amid that dysfunction, his administration launched Operation Warp Speed, the public-private partnership that accelerated the development and distribution of COVID vaccines. Trump called it a 'monumental national achievement.' Even Joe Biden, who was running against him at the time, credited the administration when he got the shot. Six years later, Trump is trashing that legacy as he courts the most conspiracy-minded factions of the coalition that put him back in office."

He added later: "While touting the order, Trump made several wildly false and dangerous claims, including the lie that vaccines are linked to autism. It's a desperate pitch to pro-Trump parents, the Make America Healthy Again movement and conspiracy theorists, all of whom distrust childhood vaccinations. Doctors are urging Americans to ignore Trump's vaccine order. Compliance with it would lead to reduced efficiency even if it was based in some sort of scientific reality."

The autism claim has far older roots: a 1998 paper by British researcher Andrew Wakefield, which the medical journal The Lancet retracted in 2010 after U.K. regulators found him guilty of serious professional misconduct. Large-scale studies since, including a 2019 Danish review of more than 650,000 children, have found no link between the MMR vaccine and autism.

Vaccines for COVID-19 were developed in a historically short amount of time across 2020, in large part thanks to the first Trump administration's Operation Warp Speed initiative. Supporters and opponents alike have generally agreed that it was one of, if not the single best achievement of Trump's first term. Now, however, as the MAGA right-wing becomes increasingly enmeshed with the anti-vaccine movement — an alliance embodied by the Make America Healthy Again movement popularized by Health and Human Services Secretary Robert F. Kennedy Jr., a longtime vaccine skeptic — Trump and his allies have grown increasingly critical of vaccinations and vaccine requirements, despite the preponderance of scientific evidence, leading them to discount or outright demonize the results of Operation Warp Speed.

"There's a real risk here," Steele later concluded. "By giving the imprimatur of the White House to these outlandish theories, Trump elevates them in the political conversation and gives them new fuel to metastasize. He turns idle chatter on the internet into official government records and undermines the serious work of historians, scientists and prosecutors. That is bad enough. But with his latest sop on vaccination to the conspiracy-minded, Trump is repudiating his own record, hurting his own supporters and putting the lives of Americans at risk."