In May 2017 the United States revealed that it had sent one of its few cyber protection teams to defend the THAAD (Terminal High Altitude Area Defense) battery sent to South Korea earlier and declared operational in April. ... To work properly the battery depends a lot of networks for quickly transmitting target and other data. Since China, Russia and North Korea all have excellent network hacking capabilities and have been hostile to the stationing of a THAAD battery in South Korea, it was expected that the THAAD networks would be subject to penetration and disruption attempts by foreign hackers.
Neither the THAAD nor the cyber protection teams have had any real combat experience. THAAD has been successful in tests but the army is still seeking a realistic way to test the effectiveness of the cyber protection teams.
Strategypage notes that creating cyber protection units is stymied by the need to hire contractors to make up for the lack of in-house talent.
This is normal for new systems. Very early in artillery introduction, artillery was provided by contractors because armies did not have the expertise.
Privatized warfare is normal. In time as the cyber capability matures, that expertise will reside in-house.
