Said if a peace deal is reached, meaning it won't be in harms way if it's lasting real peace. Peace keeping troups are different then sending them out into war which is how most made this sound when first reported.
Its already clear, that Kievan regime won't restrict themselves from attacks against Russians, and it's clear that in few weeks/months there will be rebellions in Russian-speaking and still Kiev controlled regions like Odessa and Kharkov. Ordinary British soldier can't see the difference between Vatniks and Banderlogs, so, it will be worth than Vietnam and Afghanistan (even if Russian won't do a thing about it). But more likely, facing the choice between "uncontrollable escalation" and "first strike", Russia will strike first.
We already discussed this scenario in military forum.
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Let's play the game. Just a pure intellectual exercise, nothing real about it. (Even Brits can't be that stupid).
Let's imagine, that Russia and the USA has achieved mutually acceptable solution over situation in Europe. But this solution isn't really acceptable for Kievan regime and ruling regime of the UK.
American president officially demanded from his NATO "allies" don't spoil his plan, and keep the lines. Britain, also openly and officially refused to follow American orders, and, after short but furious escalation in Baltic sea - officially declared war to Russia. British Toffs and some "regime-essensial personell" left the cities and sheltered (also, they have concealed from ten to twenty 100 kt warheads somewhere in their shelters and British cities).
Obviously, Russia by a single warhead destroyed HMNB Clyde in Scotland with two (of three) Vanguard-class submarines and [unsuccessfully] tried to eliminate the last Vanguard in the sea. No civilian losses, few thousands of British soldiers and sailors are killed and injured.
Russian government suggested "humanitarian pause" (during which both sides refrain from nuking cities and can evacuate larger part population from them) and suggested peace negotiations, including demands of British neutrality and de-nuclearisation (with Americans forces as "guarantee" of safety of the UK). And said, that for every Russian city - seven British cities will be destroyed.
British government refused and ordered to the last Vanguard all-out attack against Saint Petersbourg (for one Vanguard's salvo can't overwhelm Moscow's ABD). Saint-Petersbourg is covered with S-400, but five 100 kt warheads got through. The population is partly evacuated, partly sheltered, but civilian losses are quite terrible - like, say, fifty thousand are dead and two hundred thousand are injured.
Russian government immediately ordered retaliation strike against seven largest British cities (save from London), for the population wasn't sheltered it means millions of killed civilians. Russia demanded unconditional surrender of London's regime (with further public execution of its leaders) total international occupation of the former United Kingdom, searching for concealed nuked to prevent further nuclear terrorism.
The United States may be a part of the humanitarian occupation forces if they want it or even lead them as long as they don't try to use post-war Britain against Russia.
The choices for the USA:
1) Attack Russian Federation (first of all its nuclear forces). In overoptimistic scenario it means death of at least fifty million of Americans (and lost of the US international leading position), in the pessimistic one - total extinction of Americans (and, may be, destruction of the Western civilization and The Dark Ages for Humanity).
2) Neutrality. The USA just make few steps back, evacute US personnel and US citizens and allow Brits and Russians kill each other. It will lead to death of millions of Brits (and, may be, their total extinction) and thousands of Russians, medium risk of British nuclear terrorism in American cities.
3) The US forces (may be, with the help of international community and local British people) overwhelm British King, publically execute the limited number of British war criminals, help British people to alleviate the consequences of the nuclear strikes. For the cultural and linguistic similarity between American and British people it won't be another Iraq or Vietnam.
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