U.S. warship leads drills in Russia's backyard, a message that the Black Sea is "for everybody"

Black Sea, on board the USS Ross — A tense confrontation between a British warship and the Russian military was captured on camera late last month. Russian planes buzzed the British vessel and issued hostile warnings. The incident took place in the Black Sea, where the U.S. and dozens of other countries are still conducting military exercises.

Russia has refused to allow foreign ships to pass through what it considers its territorial waters off the Crimean Peninsula — territory that Moscow unilaterally annexed away from Ukraine in 2014. Russia has threatened to bomb any vessels that enter the area.

The U.S. Navy destroyer USS Ross left the Ukrainian port of Odessa recently to lead the military drills in the Black Sea, and CBS News' Holly Williams is the only American network correspondent on board the warship.

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This week, the Ross may have been maneuvering about 5,000 miles away from the east coast of the United States, but as America's relationship with Russia has deteriorated, the Black Sea — in Russia's backyard — has become a potential flashpoint.

Williams watched as U.S. sailors opened fire on a hostile craft, took aim at enemy warplanes and came under attack by fighter jets. It was just a simulation — a live-fire military exercise involving 28 American military allies.

But America's real-life rival appeared to be keeping careful watch over the drills. Four Russian ships took turns shadowing the USS Ross, and Russian fighter jets repeatedly circled nearby.

Commander John D. John, a 20-year veteran of the U.S. Navy, told Williams he wasn't concerned. It would take a lot more than the Russians operating close by to provoke a real clash.

"If somebody opens fire on you, that would warrant you taking self-defense measures," he said. "If somebody is aggressive and you feel threatened, you have the right to defend yourself."

When the British warship, the HMS Defender, entered the waters off Crimea last month, it was subjected to more hostile tactics in the Black Sea. The U.K. government denied Moscow's claims that Russian planes had dropped bombs in the Defender's path and fired warning shots, but the Russian military did threaten to attack.

In a radio transmission from the incident, a Russian officer can be heard warning the British vessel in heavily accented English: "If you do not change course, I'll fire."

Russia sent soldiers to illegally seize control of the Crimean Peninsula from neighboring Ukraine more than seven years ago, but the U.S. and its allies don't recognize the Russian takeover and sailing a warship through Crimean waters drives that point home.

Russia has threatened to bomb foreign warships that sail into those waters in the future. 

The training exercise that the USS Ross is participating in is several miles away from that patch of the Black Sea, and the American warship is heavily armed with Tomahawk and Harpoon missiles, and torpedoes.

Commander John calls it the Swiss Army knife of U.S. warships — well equipped to fend off aggression from enemy ships, aircraft or even submarines.

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During the "Sea Breeze 2021" exercise, the U.S. Navy has put that might on display, in part to reassure American allies.

"The message that it sends is that international airspace and waters are for everybody, it doesn't belong to one country," John told CBS News.

The U.S. says it's committed to maintaining the security of the Black Sea, and that's crucial for America's friends in the region, including many countries that live in close proximity to Russia, and fear Russian encroachment. 

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