As Washington wrangles over the technical details and diplomatic consequences of the Russian hacking allegations, there is a danger we will lose sight of the only undisputed fact: Hackers committed a series of cyberattacks to undermine the integrity of U.S. elections—and it was not hard to pull off. Regardless of who did it or why, policymakers must address America’s endemic cybersecurity vulnerabilities, writes Daniel Castro in the Christian Science Monitor.