Details

The Belgian Workers Party (PTB) and the Democratic Socialists of America (DSA) are regularly cited as sources of inspiration for a new left party and the Green Party in the UK. There are good reasons for this. They’re both socialist organizations that have enjoyed considerable membership growth and electoral success in recent years, including the election of DSA member Zohran Mamdani as mayor of New York, and 15 PTB members winning parliamentary seats in Belgium’s 2024 federal election.
Joe Todd is the former Head of Communications at Momentum and co-founder of The World Transformed, Common Knowledge and The Movement Research Unit. He blogs at New Party, Old Problems and co-hosts the Life of the Party podcast.
Particularly interesting is how they’ve achieved success while maintaining their distinct identities and practices as socialist organizations. This includes an emphasis on building ideological and committed cadres, pursuing non-electoral forms of power and taking socialist transition seriously.
However, the two organizations are very different in structure, culture and context. The PTB is a disciplined and ideologically coherent Marxist party built around a highly dedicated, militant cadre that is tightly bound to the leadership. It prioritizes coherence, continuity and top-down direction, at the cost of looser movement style experimentation.
The DSA is a broad, multi-tendency socialist organization with autonomous chapters, powerful ideological caucuses and distributed centres of power. It maximizes openness, plurality and transparency, at the cost of uneven capacity, factionalism and limited ability to direct a national strategy and programme.
Despite these differences, it is still common for people on the British Left to cite the PTB and DSA in tandem. This is a problem. As this report will show, to be more like the PTB is often to be less like the DSA, and vice versa. It’s also the case that each organization is historically and contextually specific, and it isn’t possible to copy and paste them into the UK.
This report attempts to slow the conversation down and introduce some detail. It compares the DSA and PTB as real, lived organizations with specific histories, architectures and strategic dilemmas. With an emphasis on structure, it asks what kinds of political work each is capable of doing, and what, if anything, might usefully be adapted for a left party project in the UK.


