From the Executive Summary: "The unclassified Navy-Private Sector Critical Infrastructure Game took place over July 10th and 11th, 2017. It included 125 players from 14 critical infrastructure sectors, local and state government, and the federal government. The game was designed to answer two main research questions: when do cyber attacks reach the level of a national security incident? When should the Department of Defense (DOD) be involved and in what capacity? It hypothesized that the answer to these questions would be influenced by three primary variables: the effects created by cyber attacks, the targets of cyber attacks, and the actor conducting the cyber attack.In our war game, the attacks that were most likely to escalate to a national security incident were those on the civilian nuclear sector and sectors that had strong linkages across the national economy. Attacks on these sectors with strong linkages within the rest of critical infrastructure created cascading effects, many of which had life or death implications beyond the initial scope of the cyber attack. Therefore, results from the war game suggest that U.S. government resources and policies should focus on the energy, transportation, communications, water/wastewater, and nuclear sectors. While there were other sectors that experienced loss of life, the effects from these cyber attacks were largely confined to their sector and therefore were less likely to create a national security crisis"
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