In every agency their is a rats nest that needs to be expelled before you can turn things around, these rats will be working behind the scene getting orders from head rats on the outside to disrupt and sabotage anything coming down or implemented
That is very true. Unfortunately, there is also a career group that has been corrupted over the past 20 or so years, and they have civil-service job protection, plus they are unionized through SEIU. They can be temporarily cowed, but they will work against the new order.
There needs to be a creative solution for that problem. It exists in many departments, although the most prominent are State, EPA, and Education. Lesser cleanings are needed in ATF and the Forest Service, as well.