NIGHT76 landed a while back, accompanied by GORDO15, a E-4B.
GORDO15 went south, tanked up by kC35R tanker, flew east, turned, and ran a race course around Offutt AFB and then landed.
2 E-4B's at Offutt AFB.
The E-4B has electromagnetic pulse protection, an electrical system designed to support advanced electronics and a wide variety of communications equipment. Other improvements include nuclear and thermal effects shielding, acoustic control, an improved technical control facility and an upgraded air-conditioning system for cooling electrical components. An advanced satellite communications system improves worldwide communications among strategic and tactical satellite systems and the airborne operations center.
To provide direct support to the president, secretary of defense and the JCS, at least one E-4B is always on alert at one of many selected bases throughout the world.
https://www.military.com/equipment/e-4b