” the moment countries around the world realise American security guarantees are worth fk all”
That’s a false premise.
The US has made no security guarantee to Ukraine at all.
Nothing.
Yep.....no ‘official’ (i.e., formal Senate-approved) agreements. Only Biden Regime promises (that are worth as much as the lies his BLS and Fed are told to spout).
UKR was never part of NATO, isn’t now. Never even a formally-accepted (by NATO) NATO aspirant.