The impetus was lost in 2022 when the US tied the Ukrainians arm behind its back - so to speak - by limiting long range weapons. Yet, the Russians are using weapons from north Korea and Iran to strike into the heart of Kyiv. The Ukrainians should have been given a total free hand as to how and where to strike. Kimmet and his generation of American leadership are rather poor and lack resolve. American has lacked resolve since WWII - lost Korea, Vietnam, Iraq and Afghanistan.
Unfortunately, negotiations are a ship that sailed and sank. It is sad to say, but this war will continue until one side reaches the end of its tether.