Romney is The Snake that Trump warned us about at a lot of his rallies. If Trump includes him in his administration, Romney The Snake will bite him. I can see Romney calling a press conference and denouncing Trump and resigning as Sec of State, causing a huge uproar and “scandal” of some sort that would distract the Trump administration from such things like draining the swamp, creating jobs, etc.
If Trump is serious about draining the swamp, don’t like The Snake Romney slither into that swamp.
Romney will run against Trump in the primary in 2020.