Zelinsky isn't going to be able to conquer Russia and depose Putin. Trump isn't going to be able to crush Iran and install a new government. Trump wasn't wrong in trying for peace in Europe rather than dragging out the conflict. Was he right about Iran?

Z-Man has no need to conquer Russia and depose Putin. All he has to do is a sort of enhanced Afghanistan-Russia 2.0. That is looking more and more likely.
Where Trump was wrong about Russia-Ukraine is primarily in his assessment of Russia - Putin, and somewhat in underestimating the Ukies.
Trump may not be able to “crush” Iran, but, Iran can easily be collapsed. (Not with present tactics.) The question is whether Trump is ornery enough to do it, as the civilian population would have a rough 6 months or so - much longer if they do not depose the Mullahs and IRGC.