Probably to make sure it stays that way. Logistics by ship generally has a big advantage over logistics by land. There is a rough pattern over the last century or so of the big navel empires (UK, US, Japan) having a big military advantage. In the case of the UK and US their strategic policy has a big component that involves restricting their opponents access to resources water (eg, Germany around the world wars, China in the modern era or the way the US controls the sea-based routes out of Saudi Arabia and the land routes tend to be militarily unstable).
Preventing oil exports and increase insurance premiums for Russia's export economy, because Western sanctions clearly are unsuccessful in destroying the Russian economy.
My post history shows that I do support Russia's self defense against U.S./NATO threats. In my opinion Ukraine entering NATO is indeed an existential threat to Russia, because since (at least) the collapse of the UDSSR the U.S. and it's vassals openly communicated and pursued the goal of regime changing Russia (+ Belarus, Georgia).
It's always astonishing to me how people here (mostly Americans) basically know nothing about the long history of U.S. proxy wars with Russia (historically USSR) and the long stated desire from U.S. to destroy or regime change the Russian federation.
To answer your question quickly: Ukraine entering NATO constitutes an existential threat to Russia for the same reason as China building military infrastructure in Mexico, Cuba or Canada would pose an existential threat to the U.S. (e.g. Cuban Missile Crisis).
>Ukraine entering NATO constitutes an existential threat to Russia for the same reason as China building military infrastructure in Mexico, Cuba or Canada would pose an existential threat to the U.S. (e.g. Cuban Missile Crisis).
Funny you should mention that, Russian military infrastructure in Cuba wasn't an existential threat to USA. Russia did build military infrastructure in Cuba and the US let that happen. What they did not let happen was the forward positioning of nuclear missiles during the era that Fist Strikes were still being considered. Similarly the USA has removed nuclear weapons from Russia's periphery.
I think Chinese bases in Mexico would earn Mexico a good deal of stress, but not an invasion of conquest. Of course, Trump and Putin are busy changing international norms, and I can't speak to the potentially brutal world of the future. But the history (Cuban missile crisis) suggests that USA wouldn't engage in a self destructive invasion and conquest.
Is there any particular part of the report you think I should read? The glance I gave it looks like they suggested giving arms to Ukraine to stretch Russia in the civil war they were fomenting and supplying in Eastern Ukraine at the time.
Do you consider the Putin regime as equal to Russia? Because a lot of the threats in the document are to the authoritarian system, not to Russia itself.