JPMorgan chief Jamie Dimon (left) and Chinese leader Xi Jinping (right).Win McNamee via Getty Images; Greg Baker/AFP via Getty ImagesJPMorgan chief Jamie Dimon is once again advocating for the US and China to make nice."It's the thread from Ukraine, oil and gas, food, migration, all our relationships," Dimon said.He added that he thinks the US needs "great American leadership" to stabilize its relationship with China.How the US handles its shaky relationship with China will affect the future of the world, says JPMorgan chairman and CEO Jamie Dimon."It's the thread from Ukraine, oil and gas, food, migration, all our relationships, the most important one being China," Dimon told Bloomberg's Emily Chang in an interview that aired Wednesday.