Morgan McSweeney, the former chief of staff to British Prime Minister Keir Starmer, has spoken publicly for the first time about his departure from Downing Street in the wake of the controversy surrounding Peter Mandelson’s appointment as Britain’s ambassador to the United States. McSweeney resigned in February, accepting responsibility for what he describes as a serious political misstep that ultimately contributed to the decline of the Starmer administration.

McSweeney, who played a pivotal role in Starmer’s rise to power, including managing the successful 2024 general election campaign, reflected on the pressures of the final days in government. He recalled a period of intense personal anguish, marked by guilt over the impact of the Mandelson scandal on both the prime minister and the Labour Party. “I knew the only way this problem gets gripped is if I go,” McSweeney said, describing his decision to resign after much deliberation.

Originally from County Cork, Ireland, McSweeney arrived in London as a teenager and worked his way up from modest beginnings, holding various jobs before entering politics. He built a reputation as a campaign strategist who helped steer the Labour Party away from the hard-left influence of Jeremy Corbyn, ultimately positioning Keir Starmer as the leader capable of rebuilding the party after its severe defeat in the 2019 election. McSweeney’s efforts included promoting grassroots campaigns against far-right groups and pushing for party reforms.

Despite the initial electoral success in 2024, McSweeney acknowledged that Starmer’s government struggled to meet public expectations, lacking a clear plan to enact the promised change. He attributed some of the administration’s challenges to strategic missteps, including unpopular policy decisions such as Chancellor Rachel Reeves’ attempt to cut winter fuel payments for wealthier pensioners, which was later partially reversed, and a controversy involving Starmer receiving donations for personal attire. These issues, McSweeney suggested, contributed to a growing perception among voters that the government had failed to focus on immediate concerns like the cost of living.

The decision to appoint Mandelson as ambassador to the U.S. was particularly contentious. McSweeney admitted concerns about Mandelson’s controversial associations but believed the potential benefits outweighed the risks. He questioned whether he had become a scapegoat for the fallout but emphasized that the chief of staff’s role was ultimately to protect the prime minister.

Looking ahead to the political transition expected in July 2025, when Andy Burnham is anticipated to succeed Starmer as prime minister, McSweeney expressed cautious optimism about the incoming leader’s potential, even though Burnham’s politics are somewhat to the left of his own. He welcomed Burnham’s proposal to decentralize power by establishing a prime ministerial operation in Manchester, reflecting a desire for change within Labour.

McSweeney also spoke about broader concerns regarding the future of democratic politics, particularly the impact of artificial intelligence on campaigning. He is currently engaged in projects aimed at addressing how digital technologies and misinformation could undermine voter trust.

Although stepping away from frontline politics “for the foreseeable future,” McSweeney remains reflective about his career. He credits his Labour involvement with transforming his life, from humble origins to participating in high-level decision-making with global leaders. Despite the turbulent end to his government tenure, he expressed no regrets about his political journey.