Maybe the Russians aren't all that bad...

[ChalkLine]

That and Britain loathed the Russians from the start, seeing Russian designs on India. This confrontational attitude led to them siding with the Ottomans against Russia in the disastrous Crimean War, simply because they couldn't countenance any Russian expansion.
Since then Russia has been seen as something scary, primarily because the did over Napoleon when they finally got around to fighting him properly. Important Men With Maps looked at Russia and suddenly realised how big thier manpower reserves were, and how few thier own were. The Russian Juggernaut is not just a twentieth century fear.

As far as the USSR goes, it was diametrically opposite the USA in ethos, and ideologically a bugaboo against the movers and shakers in power. The incursion into Archangel after WW1 was ideologically driven, as the commies in charge were far more democratic than the tzarists were. In fact, 'soviet' means 'council' and refers to the original pyramid democracy practised by communist groupings. It was a better democracy than ours at the time (wasn't that to change!)