What US Defense Missions Does The C-5M Super Galaxy Support?

In a recent Simple Flying article, I wrote about how the crew members of the Lockheed C-5 Galaxy (including one of my own US Air Force Basic Military Training [BMT] Military Training Instructors [MTIs]), in a self-deprecatingly humorous gesture, lovingly refer to their beloved bird as “FRED,” as in “F*cking Ridiculous Economic Disaster.” This is due to the plane’s expense and reliability issues.