Thirty years ago the great Independent European Security Identity initiative was all the rage.
The 'United States of Europe' was being sold as a counter balance to American power.
At that point, the 800 pound gorilla in Asia had not yet climbed atop the world economic ladder, although that was a work in progress.
What actually happened was that, in Europe, butter was chosen, and guns cut up for scrap.
Granted, in the 00's numerous allies were in Task in Iraq and Afghanistan, which experiences may have had, in the long term, negative impacts on defense spending's popularity. Not sure, I am guessing a bit on that last thought.