Yep, the problem with a war is that it always a 'comes as you are' deal. The only thing a nation may be able to negotiate is the date of the party or the time..and perhaps decide to show up fashionably late.
The defence cuts were short sighted and stupid, but that is irrelevant in this time and place, because they have happened. What is in the cupboard is all we have to play with, and this obviously goes for every nation, not just the UK. That said, the planned cuts of more troops, C130's etc should probably be halted immediately as they were done with a view to saving money and loss of capability was inadequately considered, or just outright ignored.
I see that Boris has already refused to agree with the Sec Def's statement today, instead saying a bunch of gibberish about defence budgets over the years etc and deflecting the question. I would not hold my breath for a ton more cash - maybe just enough so he can use the optics of it to show he is doing something. We reap what we sow, and the UK has put itself in it's current predicament, but I think it may not be as bad as some think. What would really happen if we unleashed what combat power the UK does have, against the Russians (I am not thinking 'Nuclear' - that is a game changer)? I suspect we would annihilate their air force and slaughter their artillery - it would almost be like fish in a barrel. Add in the Yanks and the rest of NATO and Russia would be eviscerated in short order, based on their performance thus far in Ukraine. But here is the thing...does anyone really believe that Russia does not know this? This is why I believe Russia will not risk a conventional war with NATO.
If a NATO/Russia war was to materialize, then I believe it inevitable that as soon as Russia started to lose decisively - the sort of loss that could not even be spun as a 'victory' by Putin himself - then he would go nuclear. If that happens, then no amount of spending will help to avert the consequences. His FM has stated in the last few days that in the event of Nato intervention this would lead to WWIII and the first place to be removed from the planet would be London.
Putin will not want to go nuclear because he is losing his forces in a conventional war - he needs a military to support his power base. Instead, he would rather jump first, nuke London (or wherever) and then immediately (perhaps whilst the missile is in the air) say 'that's it, no more will fly if you all back off and let me have what I want, and if you don't then the rest of you get it'.
I genuinely believe he is deluded enough to think he could get away with it.