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Elastomers that can sustain large reversible strain are essential components for stretchable electronics. The stretchability and mechanical robustness of unfilled elastomers can be enhanced by introducing easier-to-break cross-links, e.g. through the multi-network structure, which also causes stress–strain hysteresis indicating strain-induced damage. However, it remains unclear whether cross-link breakage follows a predictable pattern that can be used to understand the damage evolution with strain. Using coarse-grained molecular dynamics and topology analyses of the polymer network, we find that bond-breaking events are controlled by the evolution of the global shortest path length between well-separated cross-links, which is both anisotropic and hysteretic with strain. These findings establish an explicit connection between the molecular structure and the macroscopic mechanical behavior of elastomers …