The US Army Rangers and Green Berets are both elite units in the US military, but there are significant differences between them.
The Rangers are a large-scale light infantry force focused on rapid deployment for joint-special operations raids, reconnaissance, search and rescue, airborne assaults, and the seizure of airfields. The Green Berets are experts in unconventional warfare, operating in units of 12, and are tasked with six primary missions, including reconnaissance, foreign internal defense, hostage rescue, direct action, and counter-terrorism. Training to become a Green Beret is significantly more difficult than becoming a Ranger, with a one-to-two-year process split into six phases to become a skilled Special Forces member. Completing Ranger School allows soldiers to wear the Ranger Tab, while completion of the Ranger Assessment and Selection Process (RASP) grants soldiers their tan beret and officially makes them a US Army Ranger.
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