It seems to me that if ANYONE in Europe could save Nicholas and the Romanovs, it would have been their English cousins, George V. So why didn't he? Why wasn't Nicholas given political asylum in Britain following the Russian Revolution?
Two related questions:
Did George have any chance to do that before Nicholas was captured?
Was it reasonably possible for Nicholas to be able to make it to, say the UK, if he were to be offered/granted asylum?
From Orlando Figes, A People's Tragedy (Pimlico 1996), p. 636:
It had originally been intended to send the Tsar and his family to England, where George V, Nicholas's cousin, had invited him in March. But the Petrograd Soviet was adamantly opposed to the idea, insisting that the former Tsar should be imprisoned in the Peter and Paul Fortress. Moreover, George V withdrew his invitation for fear of alienating the Labour Party, although this was for a long time covered up by the shamefaced Windsors.* So it was resolved to send them to Tobolsk instead, a provincial backwater far from the influence of the revolution, where they took up a relatively comfortable residence in the house of the former governor.
My understanding is that the labour movement in the UK had a degree of sympathy for the Soviet Government, and threatened strike action if the Tsar were given asylum in the UK. Obviously, strike action would significantly weaken the war effort, and thus it was seen as unacceptable risk to the British Government. There was also the fear that accepting an overthrown, disgraced monarch into British society might embolden republicans - a particularly dangerous idea given the recent Easter Rising in Ireland.
Edit: in an effort to try and extend my answer, a quick Google search led me to a much more thoughtful response from /u/kieslowskifan last year: https://www.reddit.com/r/AskHistorians/comments/6hf14o/why_did_george_v_oppose_asylum_for_tsar_nicholas/