You're ignoring US aggression towards Russia.
The US began systematically and methodically driving Russia out of the Mediterranean Sea Region.
First by castrating Yugoslavia, secretly approaching the Yugoslav republics and pushing for their independence, then bombing the remainder of Yugoslavia, leaving Russia with no ports in the Adriatic Sea and limited ability to operate forward bases for aircraft. Then by funneling money to "pro-democracy groups" in Arab States. Obama quietly installed a puppet in Tunisia, denying Russia access to ports and potential airbases there. Arab Spring didn't work out as planned, so Obama used military force in Libya to deny the use of ports and airbases there by Russia, and then by attempting to oust Assad in Syria so the US can install a puppet and cancel the agreement for the airbase and port there.
Once Assad is gone, the US will initiate conflict with Iran in order to have highway, rail and air access from the Persian Gulf/Arabian Sea/Indian Ocean Region to Central Asia, where the US can push its hegemony and gain control.
After the US gains control of Central Asia, it will begin funneling money to "pro-democracy groups" in the eastern Russian republics, as well as smuggling weapons and supplies across the border.
As soon as Russia moves to crush the insurgent groups in the eastern Russian republics, the US (and UK) will harshly condemn and criticize Russia, probably pushing for a No-Fly Zone in an attempt to gain control. When all is said and done, the new map will look like this, with Russia losing everything east of the Urals.
Russia having access to Crimea is key to their ability to thwart US Geo-Strategic Plans.
What exactly do you think Russia should do?
Should the Russians go sit in a corner and sulk, while the US carries out its plans?
And all of this so the US Empire can expand into new markets, gain control of vital resources like timber, oil, natural gas, coal, metal ores and non-metallic minerals and send in the corporations to colonize their new found conquest so that Americans can maintain their hedonistic Standard of Living.
