The U.S. Air Force "sniffer plane" was collecting air samples off Russia's Kamchatka Peninsula on Sept. 3, 1949, when it gathered evidence of radioactivity, confirming that the war-shattered Soviet Union had tested a nuclear device. The Soviets' Aug. 29, 1949, test had come faster than expected.
Dating from the detonation at Alamogordo, New Mexico, on July 16, 1945, the basic science of nuclear explosions is more than 72 years old — three years older than the North Korean nation. Ballistic missile technology is more than 60 years old. The problems of miniaturizing warheads for mounting on missiles, and of ensuring the warheads' survival en route to targets, are not sufficient to stymie a nation — consider Pakistan, whose annual per capita income is less than $2,000 — that is determined to have a nuclear arsenal.
North Korea has one and is developing ICBMs faster than expected and with ostentatious indifference to U.S. proclamations. On Jan. 2, President-elect Donald Trump scampered up the rhetorical escalation ladder, unlimbering his heavy artillery — an exclamation point — to tweet about North Korea's promised ICBM test: "It won't happen!" It did. North Korea's most audacious act, firing a missile over Japan, came seven days after Secretary of State Rex Tillerson praised North Korea's "restraint."