They can learn a lot from the Swiss who spend a whole lot of less time and energy reacting daily to what the US thinks, says and does.
Oh, the number is zero?
Germany? Well guess what, the US has a very prominent airbase and listening station in Ramstein and a bunch of other military installations there. Also: History.
Germany would want them in Poland or such, near to Russia which is an actual threat.
Second, more to the point they have rather large military hospital there. It is also used as a safe place to transfer troops through or have them ready for outside of eu operations.
Commitment to European security would be to not support Russia. Or soldiers in Poland and Latvia. As of now, European countries paid for missiles and US is refusing to deliver.
America complained and pressured whenever Europeans bought arms from non american manufacturers. Thr first time it started to matter for real, it stopped delivering.
Some Africans started capturing American citizens and ships, maybe enslaving some, etc. Really quite unpleasant. The US eventually decided that its best option was invading Morocco.
It didn't have a commitment to defend anyone nearby, except the many Americans who traded all over the world.
The US has worldwide trade and interests now too, more so than in 1805.