  Since several years, the fragility of global supply chains (GSCs) is at
historically high levels. In the same time, the landscape of hybrid threats is
expanding; new forms of hybrid threats create different types of uncertainties.
This paper aims to understand the potential consequences of uncertain events -
like natural disasters, pandemics, hybrid and/or military aggression - on GSC
resilience and robustness. Leveraging a parsimonious supply chain model, we
analyse how the organisational structure of GSCs interacts with uncertainty,
and how risk-aversion vs. ambiguity-aversion, vertical integration vs. upstream
outsourcing, resilience vs. efficiency trade-offs drive a wedge between
decentralised and centralised optimal GSC diversification strategies in
presence of externalities. Parameterising the scalable data model with
World-Input Output Tables, we simulate the survival probability of a GSC and
implications for supply chain robustness and resilience. The presented
model-based simulations provide an interoperable and directly comparable
conceptualisation of positive and normative effects of counterfactual
resilience and robustness policy choices under individually optimal
(decentralised) and socially optimal (centralised) GSC organisation structures.
