.....Jeff Sessions.
I have no explanation for his behavior other than maybe the Left has pictures of him with barn animals.
All of those other people you listed don’t reign in the DOJ/IC. The IC regularly ignored congressional demands for information. All that we now know trickled out unwillingly over a long period of time.
Finally, Trump wasn’t really a Republican. The party was not his own yet when he took office. Many resisted him as able......ex Paul Ryan.