Why did the UK declare war on Nazi Germany but not the Soviet Union?

When the USSR invaded Finland at the end of ’39 and the Finns started doing so well against the Red Army Churchill saw an opportunity. His plan was to gain control of Narvik (northern Norway) to cut iron ore to the Nazis and then use the control of Northern Scandinavia to give significant military aid to the Finns. In effect the Churchill plan would have had Great Britain fighting the Soviets too. Chamberlain and the French went along with Churchill’s scheme. What prevented the Allies warring with the Soviet Union was the Russians finally were able to overwhelm the Finns.
I suppose what happened in europe in 1940 to the BEF and French couppled with fighting the Russains could have spelt dissaster for England so Its just as well this never happened, however it dose show that the will was there if not the means.
Churchill was more than a little upset about the post war division of Europe, it was not what he wanted at all

 

It's pretty clear that the UK had 2 different approaches to the Nazi government. The Political face prior to the war was one of agreement and appeasement whereas the Military was planning a war. A strong Germany wasn't what the UK wanted (or France) how to deal with it was the dilema. They weren't going to go away perhaps we thought that we could encourage the Russians onto our side. The Polish resistance of soviet aid in case of a German attack made it impossible for the UK to defend Poland or make early alliances with the Soviets, so the question remains did we allow Poland to be invaded in order that the Poles would require the soviets aid in repelling the Nazi attack? Thus allowing us to make a pact with the Soviets against Nazi Germany and besides up to that moment the Russians hadn't had a gloroius war record (having been beaten by the Poles in the 20's) and they had not demostrated any terriortial demands unlike the Germans. Could we have negioated with Poland to accept to give up the Polish corridor and avoid war in the way the czech lands were, would this have meant less bloodshed?
Would the Nazis have continued to demand more lands? Why did they attack the soviets and start a war on 2 fronts? Surely they would have been content with the lebensraum they had gained? How quickly did they think their frauleins could reproduce to fill these plains with Germanic kids?

 

After Hitler broke the Munich agreement it was pretty clear there was no chance of a lasting peace, he would have gone on to demand more and more concessions until someone decided to resist thus firing off the war.
As for a French intervention in the first weeks of September 1939 it could have forced the Germans to withdraw troops from Poland, but the German Siegfried line defended by some 30 or so divisions (though most still not fully mobilized) was no easy barrier to break.
But the French strategy was to wear down Germany by blockade from behind the Maginot before going to the offensive so her eastern allies were essentially left to defend themselves as best as they could, the promise of support implied by the pact with Britain and Poland was a bluff as far as short term military support was concerned, unfortunately Hitler decided to call it.

 

wow potsdammer ..food for thought.. and great choice of name.

 

From Britain's perspective:

The devil you know = Nazi Germany

The devil you don't = Soviet Russia



Or maybe they just thought they were choosing the lesser of the two evils.

An ugly choice however you slice it.

 

Well, the UK and France didn't declare war on Japan when it invaded China either. Nor did they declare war on Italy when they invaded Abyssinia. Really, with nations, declaring war is what they really don't want to do, so given that they were only compelled by treaty obligations to declare war on Germany, they weren't just going to declare war on Russia just for the moral rightness of it.

Of course the Poles hated the Russians. Not just for the backstab - before even the war, the Poles were more aligned towards the Germans than the Soviets, cooperating with the Germans in the deconstruction of Czechoslovakia, from which they in fact gained territorially. To the Soviets the Poles were always an unreliable ally, and Polish refusal of an alliance raised the spectre of the Poles allying with the Germans to allow them passage to invade - after all, a key german demand and the most public sticking point in German-Polish relations was the German demand for a route through the polish corridor, and Gdansk.

Heck, the Germans in fact pressured the Russians to follow through with their part of the agreement, and invade Poland. See
http://avalon.law.yale.edu/20th_century/ns061.asp

and following telegrams.