  Graph states are special entangled states advantageous for many quantum
technologies, including quantum error correction, multiparty quantum
communication and measurement-based quantum computation. Yet, their fidelity is
often disrupted by various errors, most notably qubit loss. In general, given
an entangled state, Bell inequalities can be used to certify whether quantum
entanglement remains despite errors. Here we study the robustness of graph
states to loss in terms of their Bell violation. Treating the recently proposed
linearly scalable Bell operators by Baccari $\textit{et al.}$, we use the
stabilizer formalism to derive a formula for the extent by which the Bell
violation of a given graph state is decreased with qubit loss. Our analysis
allows to determine which graph topologies are tolerable to qubit loss as well
as pinpointing the Achilles' heel of each graph, namely the sets of qubits
whose loss jeopardizes the Bell violation. These results can serve as an
analytical tool for optimizing experiments and protocols involving graph states
in real-life systems.
