Assertion: intercontinental ballistic missile | /r/UsedFor | more than half a century
Facets:
value: on alert twenty-four hours
type: TEMPORAL
Source sentences:
text: For more than half a century, Air Force Intercontinental ballistic missiles (ICBM), from Atlas and Titan to Peacekeeper and Minuteman, have been on alert twenty-four hours a day fulfilling their role in the U.S. Triad of strategic defense forces.