> No, armies do not have their finger on nuclear trigger with a time horizon of 30-ish minutes.
> We are not in the 1960s when at times it was literally true.
You are claiming that not only China, but the US and Russia don't have the capability of launching strikes from 30 minutes? (i.e., well beyond the time to respond to ballistic missile launch detection)? Do you have a source for this?
This doesn't appear to agree with you:
https://www.mitpressjournals.org/doi/pdf/10.1162/ISEC_a_0021...
Launch-On-Warning
One source of ambiguity in the implementation of China's no-first-use policy is the ongoing debate in China regarding the pursuit of a launch-on-warning posture. Recent doctrinal publications and Chinese interlocutors indicated that the debate has yet to be resolved. On one side, some members of China’s strategic community argued that a launch-on-warning posture would ensure the survivability of its nuclear deterrent if its opponent has robust targeting intelligence. The Science of Military Strategy states that a launch-on-warning posture "is in accordance with China's long-standing no-first-use policy, and may effectively protect China's nuclear forces from sustaining even greater losses, improving the survivable nuclear counterstrike capability of China’s nuclear missile forces." China's first priority should be to prevent its adversary from precisely locating its missile launch positions. If China is able to reliably ascertain that an adversary has already launched nuclear missiles at China, however, China could quickly launch its nuclear missiles for a counterstrike "before the enemy has been able to actually inflict nuclear destruction." Launch-on-warning would therefore provide China with an option for nuclear retaliation if a nuclear adversary were able to overcome Chinese efforts at concealment, deception, and mobility to ensure that its forces survived a first strike.
This touches on what I was talking about too. The next few paragraphs interestingly provide a counter-point that disagrees China would take this posture, but not because they don't have the capability to retaliate quickly enough, but for other reasons.