I mean yes, we did. Western Europe was unifying under Berlin in the 1940s.
> by convincing Eastern European countries to trust their protective umbrella rather than the French-German domination
Militarily speaking, modern Germany is irrelevant. (Partly due to how it’s been managed post-War.) Especially to Eastern Europe, whose security concerns require a nuclear umbrella.
Trump and conservatives complain mightily about EU underspending on defence, but that's been by American design. While the EU was/is dependent on the American security umbrella, the US had a lot of leverage over Europe. The carrot was "you don't need to spend so much on defence, we've got you covered" and the stick was "shame if we didn't have you covered anymore, since you've been underspending for so many years.