This paper revisits the dominant explanations for the underdevelopment of postcolonial nations, particularly in Africa and Latin America. Rather than attributing stagnation to “cultural inferiority” or “moral failure,” we propose that a specific psychological profile in leadership , which we call Puppet Syndrome, is a stronger and more precise predictor of national decline. Drawing on political psychology, postcolonial theory, and comparative governance analysis, we argue that leaders selected, groomed and validated through colonial and neo-colonial structures tend to present a consistent cluster of traits close to the Dark Tetrad (narcissism, Machiavellianism, psychopathy, and sadism in its structural, not purely clinical, sense). These traits are not distributed randomly; they are encouraged and rewarded in leaders whose role is to maintain external control while preserving the appearance of sovereignty. We critically examine cultural determinist authors such as Thomas Sowell, Lawrence Harrison and their followers, who attribute postcolonial difficulties to allegedly defective “values,” “time orientations” or “civilizational mindsets.” In our view, such frameworks underestimate centuries of engineered dependency, trauma-based elite formation and deliberate selection of psychologically compliant elites. They often confuse reactions to domination with causes of underdevelopment. One thing we refuse to do is to play the game of faking neutrality in the face of systems largely non-neutral by design. The article introduces two conceptual and preliminary quantitative tools: Puppet Syndrome, a psycho-political framework that links a recurrent leadership profile to economic stagnation, strategic incoherence, cultural erosion and public health deterioration. An Imperial Selection Model (ISM), which formalises how external powers tend to support leaders whose traits make them structurally reliable for resource extraction and geopolitical control. Through qualitative case material and simple probabilistic modelling, we show that where Puppet Syndrome is high, countries are significantly more likely to experience: , disproportionate trade and military alignment with former colonisers; , worsening inequality and erosion of public goods; , ritual dependence on extractive “development” models; , urban forms, education systems and diplomatic behaviours that alienate the population. We contrast these trajectories with cases where leadership remains relatively aligned with cultural memory and collective dignity, and where strategic independence is prioritised despite limited material resources. In simpler terms, this paper formalises what many citizens and practitioners already feel intuitively: it is not “African culture” or “Latin American mentality” that destroys nations, but the elevation of leaders whose psychological structure serves external interests more reliably than internal ones. Our contribution is to move this intuition from discourse to something that can be observed, coded and, eventually, measured. Keywords: Imperialism; Decolonisation; Puppet leadership; Dark Tetrad; Development theory; Political psychology.