In an ATL where nukes are delayed until around the late 1950s or early 60s due to screwups in the physics community, AND assuming history otherwise proceeds as OTL until 1945, how would a conventional world war iii turn out if the USSR decides to invade Western Europe? It must start around 1951 in the latest (WW2 TTL probably lasts till 1946 due to Operation Downfall occurring). Could either the Soviets completely conquer Western Europe or NATO be able to march onto Moscow? Or would both powers fight to a stalemate?