What are the concerns about the U.S.-Russia meetings regarding Ukraine?

The primary concern is that these meetings represent Russia achieving Putin's goal of dealing directly with the United States over the head of Ukraine and European allies. Many officials in Washington and Europe worry this could be a dangerous historical parallel to 1938, when British and French leaders negotiated with Hitler, effectively sacrificing Czechoslovakia's interests. This appeasement strategy ultimately failed, as Czechoslovakia disappeared within a year after being conquered by Germany, followed by the outbreak of World War II. The fear is that sidelining Ukraine in negotiations could similarly lead to territorial concessions and create a dangerous precedent that undermines Ukrainian sovereignty.