The way forward, Geer suggests, is not to abandon ACLs but rather to augment them with aggressive monitoring that holds people accountable for behaviors that can’t economically be permitted or denied. ACLs don’t scale because checkbox maintenance requires a scarce resource: the human decision-maker. Accountability does scale because event logging and data analysis ride the favorable current of Moore’s law.

This notion is compelling because, as Geer points out, our free society works in a similar way. We don’t have to ask permission for most things, but, “If I sufficiently badly screw up,” Geer says, “there’s some expectation that will be discovered, and I’ll be found, and I’ll be made to pay.