You forget that it's not only 1.5mln active and 2mln reserve resources. It's also around 31mln of mobilisation resource that doesn't take part in the war with Ukraine and kept for the worse scenario.Not to mention that it's also the largest nuclear arsenal (as well as a good system of its delivery). Putin's strategy is to show that he can win this war cheap and with small resources, by sending mostly "consumables" like prisoners, foreign contractors,new contractors from poor regions etc without any serious motivation,while from Ukrainian side there are good professional military+ very well motivated conscripts (who are defending their country, families, children) and they are well supported by Europe (less important) and the USA (more important).
To respond to your question: noone wants to satisfy Putin's ego. But if a foreign country sends its troops to Ukraine that means a participation in the war and already a direct threat to Russia.
If everything would be that pink as you describe,European countries wouldn't be in panic now asking Americans to protect them.
But as I said, I don't see any "threat of Russian invasion" somewhere anymore: putin is already old (he's turning 73 this year if I'm not mistaken)+time during war in Ukraine+time needed for an Army modernization etc etc and people don't really support war in Ukraine nor hypothetical WW3 if it's "Russian invasion" somewhere else. Most of Europeans seem to be also adequate enough to not start a war with Russia.
I don't want to discuss this scenario anymore, I think it's already mad and criminal even to think about it
No I haven't forgotten and there is a very good reason Putin hasn't utilised that supposed mobilisation resource, they haven't got a hope in hell of equipping them. When talking about nuclear arsenals, all other discussions become pointless, either he will use them or he won't. If he will, conventional army comparisons are meaningless, if he won't then bringing them up is meaningless. I don't think even Putin is mad enough to use nukes simply to prevent being pushed out of Ukraine.
Absolutely nothing about what Putin is doing is "on the cheap" and I find it staggering you can claim that. Russia is spending more on it's military at the moment than the rest of Europe combined, making up something like 30% of it's total expenditure. That is not cheap by any stretch of the imagination. The real reason he's using "consumables" and foreign troops is he is desperately trying to avoid having to go to the next step of escalation, which will have a larger impact on the wealthier city dwellers and his oligarch friends. He's been throwing people into the meat grinder who have no political capital in Russia and are thus expendable. Eventually he will burn through these people.
Also the reservists you mention won't be top level Russian soldiers, they will be little better than the conscripts he's already using, possibly even worse as he won't have any carrot to bribe them with, only the stick. Russia burnt through their "elite" soldiers in the early years of the war, and they couldn't finish the job against a Ukraine much weaker and less prepared than it is now.
Ah so the Russians can use foreign troops as much as they want but anyone else does and it's not allowed? Do you not see what absolute ******** that is? If North Koreans can fight for Russia, a war that doesn't involve them in the slightest, Europeans can fight for Ukraine, a war that DOES involve them.
Europe is panicking because they are woefully under-prepared due to a combination of gutting their militaries and having gutless leaders for years who shied away from any sort of conflict. An unwillingness to take on Russia is not the same as an inability to. Russia is happy to take risks and use nukes as an ever present threat to give them the security to do so. The rest of the world moved away from that after the Cold War but Russia is embracing it again. Do as we say because we have nukes.
You don't see a threat of Russian invasion? Russia has been involved in 3 invasions of it's neighbours in the last 15 years and has openly stated they want a return to the USSR sphere of influence... That's a pretty big ******* threat and there is no guarantee that threat will vanish when Putin dies. For all we know, he may not even be the most mad among the people in power in Russia and someone even worse could take over.
The only thing mad and criminal is letting Russia get away with expansionist violence. If Russia can invade Ukraine because it deems there to be a threat on it's border then European nations can support Ukraine because they deem what is happening to be a threat on their border.