I think flying a nuclear bomber over a country's sky is not saber rattling. That shit should be a declaration of war on the spot considering the current events. I couldn't even believe what I read and it was only a few hours ago. Context from another article on the news:
Japan says it scrambled fighter jets on Tuesday to respond to the approach of Russian and Chinese warplanes near its airspace, in what Tokyo called a “provocation” as it hosts a meeting of world leaders including Joe Biden.
Addressing a virtual press conference, Japanese defence minister Nobuo Kishi said that the move by Beijing and Moscow was likely planned to coincide with Japan’s hosting of the Quad meeting with its allies the US, Australia and India.
Tokyo is hosting its first ever informal gathering of Quad nations, which has seen leaders of all four nations — Fumio Kishida, Joe Biden, Anthony Albanese and Narendra Modi — meeting in the city.
Mr Kishi said Japan has expressed “grave concerns” to Russia and China over the movement of warplanes threatening its airspace, reported AFP.
He added that at least two Chinese bombers joined two Russian bombers in the Sea of Japan and “made a joint flight to the East China Sea.”
"After that, a total of four aircraft, two presumed (new) Chinese bombers – which replaced the two Chinese bombers – and two Russian bombers, conducted a joint flight from the East China Sea to the Pacific Ocean," the defence minister said.