Uhhhh ya. China has some crazy stuff and even Russias old stuff it's still crazy deadly. This isn't the movies we don't have some crazy anti ballistic missile system like iron dome
China nuking us would be like a dealer icing his most dependable junkie. Not until you're sure he ain't good for what he owes. And Russia? Eh, suicide. They don't want that.
You ever see the arms race doc, 'Trinity and Beyond' or something? During the Cold War, Soviets detonated the biggest bomb ever made, a fifty megaton hydrogen doohickey. That's fifty-million tons of dynamite, dude. Footage was probably CGI, though.