Does it really matter if the delivery system is inferior? Google says they have five thousand warheads. Even if 4900 get intercepted (98% success rate), 100 nukes will connect.
Also, besides the launch silos, there’s the bombers and the nuclear subs, which are enough to end the world by themselves
The math involved in LLMs is not complex for anyone that has passed undergrad Calc and Linear Algebra classes. If you know derivatives, the chain rule and some matrix basics you can figure them out with enough studying.
The hard part about LLMs is not the math but the neural net architecture innovations they brought (eg self-attention)