In the U.S. Marine Corps, candidates for Drill Instructor Duty are primarily volunteers. The tour of duty is three years and is widely regarded as one of the most .\r \r In the U.S. Marine Corps, candidates for Drill Instructor Duty are primarily volunteers. The tour of duty is three years and is widely regarded as one of the most .\r \r In the U.S. Marine Corps, candidates for Drill Instructor Duty are primarily volunteers. The tour of duty is three years and is widely regarded as one of the most .
