As reported by Matt Taibbi in Rolling Stone, in an article entitled "Trump has stuffed his Cabinet with tyrants, zealots and imbeciles – all bent on demolishing our government from within":
Trump's pick for energy secretary, Rick Perry, reportedly not only admitted that he didn't know what the Department of Energy actually does, but had called for that very agency's elimination as a presidential candidate (and forgot that fact during a debate). Moreover, Trump had brutalized Perry during the campaign as a dimwit among dimwits, whose "smart glasses" affectation didn't fool anyone.
For Trump and his inner circle to name Perry to any Cabinet post at all felt like trolling, like a football team wrapping the mascot in packing tape and mailing him to Canada. But to send someone you're on record calling an idiot to run the nation's nuclear arsenal, that doesn't fit easily in any bucket: mischief, evil, incompetence – it's even a little extreme for nihilism. (emphasis added)