Chinese state media has downplayed the significance of the newly unveiled strategic bomber B-21 Raider of the United States, and termed the world's first sixth-generation aircraft, as a "propaganda sample". Last week, US and defence technology company Northrop Grumman jointly revealed the B-21 Raider stealth bomber in California with much fanfare. Global Times though dismissing the publicity surrounding the stealth bomber, said, "Weapons that are considered as 'assassin's mace' of major powers are kept strictly confidential, but the marketing and promotion of the B-21 are akin to "internet celebrity." Delivering his remarks at the ceremony in California, US Secretary of…