With all your fixation on cost, you should probably look at both sides of the ledger. And asking pre-Sarkozy France or pre-Merkel Germany for help regarding Russia is a fool's errand. The U.S. should lead, because the U.S. has vital interests in the region. Your policy recommendation appears to be, "get out of their way but complain if we won't get what we need," scattered with weasel-words such as "would be far better," "should be asking," and "consensus."
The EU encompasses 27 countries with a combined population of 499 million people. They are part of the developed world with a huge economy. They are capable of defending themselves against any potential and existential threat. They are spending only about 1% on defense. They are perfectly capable of defending their vital interests, especially if the US provides the nuclear umbrella and remains committed to such organizations as NATO.
My "fixation" with costs is firmly rooted in reality. The US is sinking under an ocean of debt. And we have the perfect storm brewing with the coming bankruptcy of our entitlement programs in less than a decade. The UK had to make some choices on its global presence, e.g., no troops east of Suez, when it realized it could no longer afford guns and butter. We are heading in the same direction and matters will be made worse if Obama is successful with his healthcare and cap and trade programs.
The Soviet Union spent its way out of existence. The US will be faced with some very hard choices in the not too distant future. And it wouldn't matter who was President. The chickens are coming home to roost as a result of our profligate ways. Adding to that is our importation of poverty due to our pro-population growth immigration policies that bring in 1.2 million legal immigrants annually, most of whom are poor and undeducated and will represent a net drain on our economy. We will add another 135 million people in the next 40 years or the equivalent of adding another France and Germany to our population, 75%due to immigration.