Which most Westerners didn't care about. Stalin had begun his policy of 'socialism in one country', which meant that the Soviet Union was regarded as less of a threat to the West than it had been under Lenin's and Trotsky's rule. The demonisation of Stalin in the West only really got off the ground during the Cold War, from 1947 onwards.
Yes and no. The American public did not really care about the USSR until the Truman presidency, yes. However, to say they were regarded as less of a threat is a bit of a stretch. In fact, during the war, Churchill proposed "operation unthinkable", which was a proposed invasion of the USSR by the UK and United States. In fact, Churchill came out and said after the invasion of the Soviet Union by the Germans: "If Hitler invaded Hell, I would at least make a favourable reference to the Devil in the House of Commons."
You seem to make it seem that Stalin wasn't a huge threat to the world. In fact, he was, and in fact, it was Stalin and the USSR, in turn, that was one of the reasonings behind appeasing Hitler. So no, Western governments DID care about the Soviet Union and were directly, and indirectly, already engaging in Cold War policies during and before WWII.