Well he wasn’t able to stop the Afghan war. And so far Zelenskyy has said recently that no negotiations for the end of the war that do not include Ukraine are even worth talking about… as Trump decides to only include the invader Putin who helped Trump win the elections in 2016.
Everyone was very unable to cope with the afghan war, the worst one was Biden with the disastrous withdrawal, second in list Obama, who by his public announcement of future troops withdrawal warned the Talebans to start and prepare their comeback. LAst, Trump, the best of the three, but even his administration probably erred in letting the Talebans out of their jails to start negotiate with the legitimate government. But Trump at least tried a reconciliation strategy, the others only brought about disasters, although one of them had a Nobel prize for peace.
Ukrainian negotiations: Trump will lead them, not Putin, but a deal is a deal, the parties directly interested in the deal are two: Ukraine and Russia, so Trump will necessarily listen to Zelenski, the deal will have to appear fair.
Mr. Trump has a huge ego, so he will try to do his best to show that he has been able to stop that war at fair conditions and to be able to claim legitimately the Nobel prize that was delivered to Obama for doing basically nothing, by a weird committee, whose reasons are the following platitudes:
For his extraordinary efforts to strengthen international diplomacy and cooperation between people.