Just curious. Could President Xi save face and not lose credibility if he were to order the detonation of a full-yield DF-41 warhead(s) (a test similar to the 1966 one involving the DF-2) over Nop Nur once Pelosi arrives in Taipei?
Another option could be to fly two (one launch from TEL, the other from a Silo or train) DF-41s carrying dummy warheads over Taipei and the Australian Capital toward South Pacific in full-range tests to demonstrate DF-41's capabilities?
Could these be face-saving options should Pelosi press forward (which is the likely scenario now)?
China doesn't do nuclear testing anymore.
China has no first use for a reason. They always reserved the idea to destroy enemies using conventional force only, to minimize the chance of MAD. Nuclear threats for indiscriminate destruction isn't what China does, China does highly precise conventional threats.
For this case, it is likely confirmed that China will intercept the plane, but unless US military enters Chinese airspace, they'll probably not fire on it. They may fire on ROC fighters if ROC sends fighters. More important counteractions are seizing territory across the straits, making patrols over Taiwan routine, declaring partial sea/air blockade etc.
It's actually extremely easy for the government to save face, they just need to act appalled and then raise the budget like how Scholz in Germany acted when his nation was caught completely pants down from Ukraine being invaded. They'll win sympathy points from the population, and if Xi then promises remilitarization, then it could even improve his chances to get a third term.