Sinn Féin, Ireland’s most popular party by a narrow margin according to a recent opinion poll, has experienced a significant decline since its peak support following the 2020 general election. Despite winning the highest number of first-preference votes in that election, the party was unable to form a government. Its support rose to approximately 36 percent by mid-2022, at one point surpassing the combined backing of the two long-established parties, Fianna Fáil and Fine Gael. However, this momentum faltered sharply, leading to a disappointing result in the 2024 election, where Sinn Féin finished third in the popular vote.

A new book by Siobhán Fenton, former deputy head of press for Sinn Féin in Dublin, provides a detailed insider account of how the party’s prospects unraveled. The book portrays a party that had confidently prepared for government but found itself in a “funereal” mood following the 2024 defeat. It suggests that Sinn Féin missed what many regarded as a once-in-a-lifetime opportunity to break the near-century-old dominance of Fianna Fáil and Fine Gael and to potentially establish itself in government both north and south of the Irish border, a historic milestone 26 years after the Good Friday Agreement.

Fenton’s account points to a series of strategic missteps and a growing disconnect between Sinn Féin’s leadership and its core working-class constituency. The party, once noted for its grassroots activism and clear focus on the country’s housing challenges—which had been central to its rise—made key errors during its campaign period. One major miscalculation involved party leader Mary Lou McDonald’s public stance on housing: she proposed reducing excessively high house prices to €300,000, without fully acknowledging the concerns of current homeowners who feared negative equity. This issue was underscored by an incident at a pre-election press conference where policy booklets physically fell apart, a moment described as metaphorical for the party’s position.

The party’s handling of the 2023 Dublin riots also attracted criticism. Sinn Féin’s attributing blame to authorities was seen as politically damaging and alienated some segments of its support base. Additionally, the party’s increasingly hardline position on immigration clashed with the perspectives of some traditional voters. Fenton recounts personal experiences on the campaign trail where hostility toward Sinn Féin was palpable, including being pelted with coins and accused of betrayal.

McDonald, who had been widely expected to become Ireland’s first female Taoiseach, has retained leadership despite the setbacks. However, Sinn Féin’s support has declined to around 21 percent, and questions remain about the party’s ability to recover and secure power in future elections. Fenton’s narrative offers a straightforward chronology of the party’s decline but is less definitive about whether Sinn Féin can learn from its recent errors.

Reflecting on the wider political landscape, Fenton references the resignation of former Taoiseach Leo Varadkar in 2024, suggesting that political fortunes are cyclical. For now, Sinn Féin’s longstanding ambition of governing across the island remains deferred, with the party facing the challenge of rebuilding trust and reconnecting with voters amid a shifting political environment.