Only, ask your military to return against your just previous allies (at your own initiative) among which the one that helped your very nation to fight for its independence, with which you did cross-training and exercises, for the past 80 years... everyone is in for quite a bumpy road.

And, I was more thinking of the situation on American ground, within the USA and between the USA and Canada. I don't mean it wouldn't happen. I mean that I don't think that would happen with 100% engagement from all US army. The disconnect and reversal of strategy of the US, against its own allies, is too sudden.

Do you have any numbers or analysis to back this up, please?

A few counterpoints:

- Russia failed to 'take' a relatively unprepared Ukraine, and arguably has only managed the gains it has made because the support (from Biden US and EU) was drip-fed according to the Biden team's strategy.

- Russia is haemorraging fighters and modern fighting machinery in the current war in Ukraine. It's unknown how much longer the loss of life can be sustained without internal unrest. The absence of modern machinery would obviously make an invasion of Europe less likely to succeed.

- While Russia might now be a "war economy" I've seen reports that they can't economically sustain the war for too much longer.

- While the EU certainty needs to invest in defence, some countries are already strong, and would likely fight to protect the collective.

Overall, this suggests that Russia would fail against a united Europe, were they to extend beyond a defeated Ukraine.