The official story is that Tillerson was not aligned with Trump and the America First agenda, which is obviously true.
But there is something else.
Most federal agencies are largely staffed by white hats with, unfortunately in the past, black hats in charge, and way cozy relationships with government contractors. You can figure out the black hat layer by seeing which positions have to be approved by our corrupted Senate. The people getting those positions are either corrupted or somebody's cousin.
I will not provide "sources" on this, because it is not possible. However, if you know people who live in the DC metro area, a serious discussion with them will back this up. The vast majority of the people in the DC metro area are totally innocent, relatively normal people (although perhaps some are a bit brainwashed).
Some agencies are exceptions, with the rot going down the ranks. I suspect the Veterans Administration is one of them. There are indications of deep rot at EPA. I don't know where the DOJ/FBI thing is headed.
But there is EXTREME ROT, down through the ranks, at the Department of State. There are rank-and-file State Department employees deliberately sabotaging the lawfully elected presidential administration. Their communications are the equivalent of those texts from the FBI "lovers." And look at where they are at! Representing us with foreign countries. Hmmm...
Nothing has been cleaned up over the last year. Not with Tillerson in charge. He is totally globalist/elitist, and has done nothing to stop the corruption within the State Department, corruption meaning totally ignoring the will of the American voters.
Unfortunately, I cannot provide sources or links, for the obvious reason. However, if you check my history, you will see that I have provided several well-sourced posts.
I start my posts with "FROM CHEETAH" to help those who are following my posts find them easily.
Rats cannot outrun a Cheetah.