Municipal Socialism’s Tests: Spain’s Lessons for Mamdani’s NYC Governance

Barcelona and Madrid Mayors Show Pitfalls and Possibilities of Left-Wing Urban Leadership

Spain’s Left Mayors Offer Cautionary Lessons for Mamdani’s Ambitious NYC Agenda

Barcelona and Madrid Experiments Illuminate Both Opportunities and Dangers in Left-Wing Urban Governance

As New York City prepares for Mayor-elect Zohran Mamdani’s January inauguration, observers across the ideological spectrum have sought historical parallels to understand what a democratic socialist leading a major American city might accomplish. While some have referenced Milwaukee’s early 20th-century “sewer socialists” or invoked images of the Paris Commune and Red Vienna, a more immediate and instructive comparison emerges from Spain’s recent municipal governance experiments. Following the 2015 anti-austerity indignados wave, two major Spanish cities—Barcelona and Madrid—elected left-wing mayors who faced challenges remarkably similar to those Mamdani will encounter. Ada Colau’s Barcelona en Comú and Manuela Carmena’s Ahora Madrid coalitions swept into office on platforms combining housing activism, public service expansion, and resistance to European austerity orthodoxy. Both campaigns assembled broad coalitions of younger, middle-class voters affected by austerity, working-class communities, and centrist voters seeking alternatives to establishment politics. According to reporting from Jacobin magazine, both administrations quickly discovered that executing ambitious reform agendas within the constraints of municipal governance presents profound challenges. Carmena’s Madrid administration provided perhaps the most instructive cautionary example. Though the mayor enjoyed initial symbolic successes—visiting poor neighborhoods on her first day in office, riding the subway to work rather than using official vehicles—the administration encountered systematic obstacles that gradually constrained its ambitions. Spain’s finance minister Cristóbal Montoro imposed spending restrictions on the city under 2012 budget stability legislation that limited municipal fiscal autonomy. Facing monthly interventions that threatened service disruptions, Carmena’s government confronted a fundamental strategic dilemma: whether to stage confrontational resistance or accept constraints while advancing what remained possible through institutional channels. Jacobin reported that Carmena ultimately selected caution. When Montoro demanded a 7.2 percent budget cut in November 2017, the mayor accepted the restrictions rather than orchestrating coordinated resistance with other progressive municipalities. Though some Madrid officials, including finance chief Carlos Sánchez Mato, advocated for a more combative stance—forcing Montoro to unilaterally impose cuts rather than accepting them voluntarily—Carmena’s instinct toward institutional politics prevailed. This decision, though pragmatic, carried political consequences. The administration lost crucial anti-austerity credibility with its activist base and more radical coalition members. The choice to maintain fiscal discipline while accepting cuts signaled that the city would not meaningfully challenge central government orthodoxy. Subsequently, as internal divisions deepened between moderate and radical elements within Ahora Madrid, the coalition fractured. Carmena’s 2019 reelection campaign adopted a depoliticized tone emphasizing technical achievements like pollution reduction and participatory democracy rather than systemic challenges to austerity. The result proved counterproductive: the center-left Socialist Workers’ Party absorbed moderate votes while progressive abstention in working-class neighborhoods cost Mamdani’s ideological cousins the election they might have won. Colau’s Barcelona experience, by contrast, offers a more instructive model of sustainable left-wing urban governance. Though Barcelona faced fewer budget constraints due to lower municipal debt, the city encountered different obstacles: relentless legal challenges from corporate developers, hostile media coverage, and binding contracts that prevented easy reversal of previous privatization decisions. Rather than being cowed by these constraints, Colau’s administration methodically advanced a housing and social policy agenda across two terms. The city implemented an ambitious Right to Housing Plan that increased social housing stock by 80 percent, though critics note this expansion began from an extremely low base. The administration pursued aggressive anti-Airbnb policies, licensing regulations that restricted new tourist accommodations, and mediation programs that halted evictions in 90 percent of cases the city’s administration addressed. When Colau encountered legal reversals—particularly the court ruling against Barcelona’s authority to regulate rideshare platforms—she leveraged public pressure and external events (specifically a taxi strike paralyzing the city) to pressure regional authorities into implementing regulations. Colau succeeded partly through superior internal cohesion. Her hegemonic position within Barcelona en Comú, combined with a more integrated leadership team and organized base, created stability that Carmena’s ideologically fractious alliance lacked. Additionally, Colau possessed greater budgetary autonomy than Carmena, reducing pressure to accept central government spending constraints. Equally important, Colau explicitly positioned her administration against “economic elites” and maintained this populist framing throughout her tenure, even as she made pragmatic compromises. She combined technical competence in governance with clear naming of adversaries—real estate speculation, international investment funds, tourist overcrowding—providing political coherence that sustained constituency support. Yet even Colau’s more successful tenure encountered fundamental constraints. International capital found novel mechanisms to circumvent housing regulations—student co-living units, temporary rental markets serving digital nomads, corporate landlords shifting to short-term rentals—allowing speculative dynamics to persist despite the city’s efforts. Colau’s deputy mayor Gerardo Pisarello noted that the 2015 electoral coalition lacked social depth: “We had votes but no organization.” This weakness limited the administration’s capacity to generate constituent pressure for more aggressive action or effectively counter hostile media narratives about Barcelona’s governance quality. The Spanish examples illuminate critical challenges awaiting Mamdani. First, left-wing municipal governments inevitably confront significant structural constraints—national budget rules, corporate litigation, media hostility, and limitations on formal municipal authority. Unlike Carmena, Mamdani possesses advantages: stronger ground organization capable of mass mobilization, absence of European Union austerity rules, and a more coherent political coalition. However, he faces a Trump administration explicitly hostile to progressive urban policy, creating federal obstacles that exceed Carmena’s constraints. Second, sustaining momentum between campaign promises and governing realities requires constant expectation management. Colau succeeded partly by framing partial victories as significant achievements while honestly acknowledging limitations of municipal power. Carmena struggled because she made ambitious campaign commitments without clearly explaining how municipal government’s limited authorities prevented full implementation. Mamdani’s proposals—free city buses, universal child care, rent freezes—each confront practical implementation challenges he will need to navigate transparently. Third, internal coalition cohesion matters enormously. Colau’s ideological hegemony within her coalition created stability; Carmena’s fractious alliance between Podemos, Greens, and Trotskyist elements produced paralysis at critical moments. Mamdani’s progressive coalition, while broad, contains both pragmatists and radical elements with differing expectations about how aggressively the new administration should challenge established institutions. Finally, left-wing municipal governments require robust ground organization and social movement engagement beyond electoral support. Both Colau and Carmena faced media narratives of chaos or dysfunction that limited their political capacity. Mamdani’s stronger organizing base could potentially prevent such narratives from taking root, but only if the ground organization focuses on defending municipal initiatives rather than fracturing over inevitable compromises. Jacobin’s analysis suggests that Colau ultimately proved more successful than Carmena, not because she avoided constraints but because she combined competent governance, clear political messaging, and willingness to wage selective confrontations with adversaries. For Mamdani, the Spanish mayors’ experiences suggest that ambitious progressive urban governance is possible but requires exceptional political skill, organizational discipline, and realism about what municipal power can achieve. The next eight years will test whether Mamdani can navigate the narrow path between cooptation and collapse that confounded or defeated his ideological predecessors in Madrid, though Barcelona’s example offers some grounds for believing that success, while difficult, remains within reach.