Imagine this was 1944, and the Allies were slowly but surely starting to defeat the Nazis; but then in the middle of the complex war, a new US president came into power, and he suggested that Europe should now achieve peace by letting Hitler keep France, Belgium, The Netherlands, Denmark, and Poland.
We Europeans would laugh at that president. Just like we are laughing at Trump right now, for suggesting we should let the modern day Hitler keep Crimea, Kherson, Zaporitzjzja, Donetsk and Luhansk.