First of all, I think that continental Europe always has seen itself as the great loser in a future NATO-Warsaw Pact conflict. Even in the case of a conventional war, nothing would save Central Europe from the destruction of war. And about the terrible specter of a nuclear war, we are only first seat spectators totally tied to the will of others. In the situation described in Twilight, any of the signs from any of the former soviet republics to get closer to Europe or NATO would be seen as a problem. So, do not expect much effective support to countries like Ukraina and Belarus when (in v2 timeline) they begin their separatist movements. The public sign of the Treaty of Public Security, the New Warsaw Pact, could be the first warning that forces European diplomacy to take some decisions. But we are so slowly... Belarus will fall in notime, just like Poland did in 1939. First political pressures over Germany to prevent their agressive politics against Poland must be expected.
Of course, everyting will change with the effective beginning of the hostilities in Europe.
Here, some thought about innner politics:
I think we can simplify in some way the political map in Europe. Although the apparent complexity of this map, Western European states are always playing to the game of coalitions and, in most cases and no matter the number of parties in each country, you will encounter two different political blocks with moderate differences between them if compared to other moments in our histories. In a lot of countries, the presence of one party or another in the government are subject to the attitude of minority parties, but, in resume, a lot of countries in Europe are based in two-party coalition. I know I'm simplifying the question too much. But what I want to state is that, broadly speaking, any government that supports Germany at the outbreak of the war would be in internal political disadvantage. If the country in question has important parties representing old nations in a modern state (like Spain) , the differences would be greater, because such parties are always reticent to support the politics of the state where they belong in support of foreign wars. The balance of power will change accordingly to the political support to Germany. This change would cause the abandon of NATO in some cases. If the government insist in supporting Germany and enter the war its position will be, at least, very uncomfortable. At worst, the power would eventually change of hands due to popular pressure and the political maneuvers of the opposition.
A second important point. What Western countries understand as heavy military casualties will be nothing compared to what they will encounter in the first stages of the war. Even with NATO forces gaining the upper hand in Poland, the continuous dripping of inevitable casualties would be an added factor to the pressure borne by the governments that have decided to joint the war. Any attempt to mobilize more soldiers, if not justified as a self-defense against an aggression or as internal security force, could end in riots.
Of course, some countries would adopt a mid-way position. They will provide logistical support and their bases inside their boundaries, but without sending troops to the front. More possible Spain would be in this grey zone.
Diplomatic pressure from the more implied countries must be expected, but the inner public opinion has more chances to prevail. And even for those governments who are sending troops,there's no point risking to provoke a change from an ambiguous government to a totally reluctant one.
And another important point. Before July 9th 1997, NATO divisions are closing up to the Polish-Soviet frontier... Although not very obvious this will be another political friction point. If NATO has entered the fight to prevent "Germany desmembration as state", if NATO troops are in the russian border and if the soviets seems to be in a critical position in China...some of the western allies could think that this the right moment to look for a cease-fire, isn't it?
But then, war becomes nuclear...in another post
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