Axes of evil. Four days, two murders, and one poplar tree that almost ignited World War III.

The poplar was a problem. One of the few survivors from a deciduous forest bombed into oblivion during the Korean War, the tree towered 40 feet over a stripped, scrubby landscape; in the summer, its leaves formed a thick green crown. A stranger to the Demilitarized Zone (DMZ), the skinny belt of no-man’s-land that has divided the Korean peninsula since 1953, might have seen this as evidence of nature’s resilience. To the U.S. soldiers patrolling the area, however, it represented a conspicuous security risk.