Ukraine is critically important to Russia. Much of Russia’s Black Sea Fleet, responsible for naval operations in the Black and Mediterranean seas, has been based there since it was part of the soviet Union. That puts critical Russian assets near Bulgaria and Romania, where hundreds of Marines are based.
Heightening tensions between the U.S. and Russia are recent incidents on the Black Sea. On May 30, a Russian fighter jet buzzed by the Navy’s destroyer Ross. The Navy released video of the incident after Russian state media reported that the Ross was in or encroaching on territorial waters. Russian officials alleged that the fighters were scrambled to force the Ross to change course. Navy officials dispute all facets of the claim.