How Iran used US troops’ digital footprints to hit Mideast bases for billions in damage

When Iran’s military planners prepared to hit American bases in the Middle East, they relied on intelligence from an unlikely source: US service members themselves.

According to security experts and even the US military, Iran harvested data from social media accounts, fitness apps and even ads to establish patterns of life in US bases across the region.

Paired with imagery reportedly provided by Russian satellites, the Iranians selecting the targets constructed a surprisingly accurate picture of...