The country has Europe's largest supply of uranium, second-largest supply of natural gas, and substantial reserves of lithium and other rare-earth minerals. These resources are valued at about $1 trillion, and about a third are in Russian-occupied territory in eastern Ukraine.

Mr. Trump wants a share of those resources as repayment for the aid the U.S. has provided Kyiv during the war. This is the transactional way Mr. Trump views the world and it smacks of reparations, but Mr. Zelensky had little choice other than to oblige if he wants to secure a credible "peace" with Russia. Mr. Zelensky was at least able to negotiate better terms than Mr. Trump first demanded.