Our NATO allies don't spend nearly as much as America does.
As a percent of their GDP, few NATO members reach the 2% threshold goal that NATO says is the minimum.
Yet the numbers are a bit misleading, given their focus on the input rather than the output.
For one thing, we have a national interest in keeping Europe's immense economic, scientific, and human resources from being controlled by a hostile entity regardless of whether Europe adequately defends itself from such an entity from external sources.
So failure of Europe to spend doesn't relieve America of the need to spend.
As for European spending itself, for most countries the spending over-states the military capability created because many of Europe's legions of troops are civil servants in drab uniforms.
So under spending the goal misses how bad these countries really are, defense-wise.
As for Greece exceeding the threshold? Don't get excited. Greece spends with an eye to a possible war with their technically NATO ally Turkey.
Estonia? They are so tiny that while they are to be commended for exceeding the threshold, it doesn't mean much compared to their Russian neighbor's capabilities.
And America's spending obscures as much as clarifies what we get.
Britain suffers from a lot of America's spending needs in regard to power projection and nuclear weapons, but on a lower scale.
Kudos to Poland. A bit. But being a neighbor and serial victim of Russian conquests in the past makes me think that Poland should be able to devote at least as much effort as Greece does to warding off Turkey, don't you think?
Given the reality of spending and scale, only some European countries should be encouraged to build militaries that are capable of joining us in war with their own section of front.
Britain, France, Germany (because of their large economies), and Poland (because of their location) are prime candidates for this tier of capabilities. Italy should be on this list, but I don't know if they could make the effort--even if they want to--given their financial fragility.
But smaller countries shouldn't be encouraged to waste their efforts for this status. They should be encouraged to integrate their militaries with America's military in order to get more bang for the buck in local spending.
Why should these countries spend on a logistics and administrative tail that supports a tiny tooth that will never wage war alone, when these small states could essentially be tribal auxiliaries attached to American units?
And forget the notion of trying that amongst European states. That's a waste when you consider that without America, a bunch of weak European nations that integrate weak militaries will still have a weak continental military.