There is widespread agreement within industry and government that the United States needs to strengthen its position for deterring cyberattacks from foreign adversaries, yet the process for developing such a widely supported policy remains unresolved even after years of debate, legislative action and an administration intent on demonstrating a get-tough resolve in countering cyber threats. The lack of an effective U.S. deterrence policy negotiated with like-minded allies was highlighted in a recent speech by Sen. Mark Warner (D-VA), billed as...