I believe Britain and other nations that support this country in applying reciprocal action against Russia for the use of a nerve agent on British soil may well find themselves involved in a new cold war in the very near future. Putin and his government have been given much encouragement in recent years in believing that acts of aggression can be carried out on foreign soil without risk of any meaningful reciprocal action being carried out against Russia.
In the above, I would cite the Russian invasion of the Crimea, the downing of an airliner over the Ukraine and it's continuing action to destabilise former Soviet Block countries surrounding the Russian Federation borders. Therefore, on this occasion i believe the British government in stating that without doubt Russia is responsible for the nerve agent attack in Salisbury.
Britain has received nothing but "mocking" comments from the heavily state influenced Russian media and the remarks from the Russian Embassy in London have been nothing short of a total insult to those suffering pain, ill health and distress following the Salisbury attack. Therefore, I feel the current policy of "appeasement" towards what has become a dangerous rogue state by Europe and the United States must now come to an end.
In the above, I believe that there is much in common with the policy of "avoiding confrontation at all cost" applied by Britain and other European countries in the 1930s, and a similar policy carried out in recent years towards Russia.
That appeasement policy failed in the 1930s, it again has failed now.