That’s the problem. How would he have known who to fire?
Tillitson didn’t have that knowledge.
Clinton fired all of the US attorneys. Trump hasn’t. Nor has he cleaned out other agencies wholesale.
That would take a bit if in depth work, but, I would say this:
As to the Ambassadors it would be easy: If it was a political appointment, made my Obama, they are automatically gone.
If they are a career State Dept. appointment then it is a bit tougher, but he could have looked at: Their resume, who appointed them and who they have made campaign contributions to. Their are people inside these agencies who could have provided deep background, not directly to Trump, but to his advisors.
Then there is this: When in doubt, fire them anyway.
Yes, he did. As very president does.
2017 dismissal of U.S. attorneysAll but three of the requested resignations were accepted.
From Wikipedia, the free encyclopediaOn March 10, 2017, Jeff Sessions, who was appointed United States Attorney General by President Donald Trump, requested the resignations of 46 United States Attorneys.[1] Some resignations were declined by Sessions or Trump.[1][2] Media outlets described Sessions' move as abrupt and unexpected but not unprecedented. It is typical that when a new president enters office, that many sitting U.S. Attorneys depart on their own initiative before their term in office has concluded, or they are asked to resign. The other 47 U.S. Attorney posts were either already vacant by the end of Obama's administration or the incumbent U.S. Attorney had resigned at the beginning of Trump's administration.