The whole arms race and physical war is just a smokescreen for the real war that is happening in the background. That war is happening in the cyber/internet landscape, infrastructure, politics and economics.
In terms of dealing with Europe and the west Russia does not need to build a single tank. It just has to propel the right people in the right places into power. Russia already has a Russia friendly US president and they'll potentially soon have a Russia friendly UK PM. Clearly it is winning whatever it is doing to influence that.
Unfortunately this is our own fault. We surrendered our defence industry to cost long ago and we have already caved every other industry into the lik es of China. Our politics is also being surrendered to misinformation and crap on social media and we're completely addicted to it despite having the outright power to turn the bloody thing off.
Our ability to make war has also been reduced to nothing. In WW2 they were building nearly 100 Spitfires per week whereas it now takes 2 years to build a single £100m fighter jet. Our main fighter jet is built via parts sourced from Europe, a dance of multiple points of failure/vulnerability. Our other fighter jet depends upon whether the US administration of the day will allow us to use it because they can just stop supporting it if demanded.
If war does kick off then it won't be a war that anybody can win quickly. Because we can't sustain war it would be equivalent to what we see now in Ukraine, trench warfare, drones, a war of simple makeshift and manpower which means a bloodbath of equivalence to WW1... and that's until the nukes start firing. Anyone wishing for this is just completely mad and thankfully even the Russians aren't that mad.