That's what I also mentioned in my first reply, just without the specific Putin, etc. instances.
Honestly, any worse than Trump? Let's face it, Russia, Iran, NK are outliers on the global front when it comes to diplomacy. I don't see any of those examples listening to DJT or being swayed by him. Certainly Oprah wouldn't hold less credibility with those, but she would hold a far greater amount of credibility with more mainstream diplomatic partners and be better equipped to work with them than DJT will be, a net benefit.
As far as the military is concerned -- is Trump any more respectable than Oprah when he's rage tweeting about bringing us to the brink of nuclear war? Is that something that should make our troops want to stand in line behind him? He wasn't any more qualified to be Commander in Chief than Oprah would be, although I'd imagine her behavior and ability to take sound advice to be far greater than Trump's.
As people said, would her skills translate over?
Can you see Oprah standing up to Putin? Iran? NK? Being Commander in Chief ordering slowguy and our military around?