If you want to know what a WW3 looks like in a post cold war, post MAD, post war on terror era, then look no further than current events. Non official cover, "sardaukar in harkonnen livery", NATO soldiers rebranded as mercenaries fighting in ukraine to kill russians, to Russians kicking out NATO in africa, to NATO-French-CIA retaliating by attacking Russian mercenaries in Africa and sending POWs to ukraine.
This is typical of a bully who pushes you and pushes you and i hate to say it but Russia is forced to do this because unlike China, it doesnt have anything between military units/army to strategic nuclear weapons. China on the other hand, knows how to deal with greyzone warfare; the PLA via the PVA were the original "sardaukar in harkonnen livery" in Korea and its gargantuan Coast Guard ships dwarf whatever the USNavy wants to send forth as a show for its mail order brides in the Philipinnes (strangely, that US Coast Guard ship was missing when a filipino lost his finger).