U.S. Ambassador to the United Nations Linda Thomas-Greenfield joins Andrea Mitchell for an exclusive interview on the first anniversary of the war in Ukraine at the United Nations Headquarters. Regarding China advocating for peace, Thomas-Greenfield said, “If they are serious about peace, then they would not consider providing lethal weapons to the aggressor, in this war. We all want peace.” She added, “This is why we've made clear that that is unacceptable, that they cannot engage in with the aggressor on this war. And Russia is the aggressor.”