Putin has moved the goalposts of the conditions under which Russia would launch a first nuclear strike. His threats are deliberately ambiguous and dangerous.
Until now, Russian nuclear doctrine consistently stated Russia would only use nuclear weapons first should the existence of the state be threatened, rather than its territorial integrity'.
However, the planned referenda which aim to annex parts of Ukraine would mean any Ukrainian attempts to reclaim that territory could then be framed as a threat to Russia's territorial integrity.
The impact of nuclear weapons use would be grave and would require a strong response - and therefore could escalate quickly to become a large-scale regional war and possibly all-out nuclear war.
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