From the Background: "The Department of Defense notes 'military operations in Iraq and Afghanistan, and many future operations will center on developing capability and capacity of host nation (HN) or other FSFs [foreign security forces].' SFA [Security Force Assistance] activities have and are occurring in Africa, Europe, Asia, and South America. In the past, Special Forces units handled the majority of SFA missions, but the growing requirement for SFA over time has resulted in conventional forces assuming a more active role in conducting these missions. Conventional forces SFA missions were normally assigned to a Brigade Combat Team (BCT), the Army's principal warfighting organization. Because of the nature of SFA missions, BCT leadership--officers and senior and mid-grade noncommissioned officers (NCOs)--were typically deployed to conduct SFA missions, with most junior NCOs and soldiers remaining at their home station. This situation, while practical from a resource perspective, created a number of readiness concerns for the BCT soldiers remaining at home station. One such concern is with leadership stripped out of the BCTs for the SFAB mission, the remaining soldiers were limited to training at individual and squad level only, resulting in a low level of unit readiness."
CRS In Focus, IF10675
Congressional Research Service: https://crsreports.congress.gov/