Trump can appoint the heads of the Agencies, but apparently has to power to fire the staffers who are doing this internal political work.
I would like to see either,
A.) they be reviewed for misuse of company resources to conduct illegal surveillance of domestic target for political purposes, and be fully prosecuted or at least fired, or
B.) Meet the same end as the other CIA agents in the opening scenes of 3 Days of the Condor, and get a visit from the angry mailman.
The CIA has a very important role, but spying on domestic targets for political purposes is not one of them.
Yes, the Senate needs to start a thorough investigation, not seen since the Church Commission.