Amping up military production is basically a reaction to certain countries electing maniacal pedos as presidents instead of jailing them.
Making a car and tank has way more in common than making a car and a CPU.
An Abrams has a multi-fuel jet turbine that’ll take diesel, gas, and jet fuel; all of which are easy to transport and store in bulk, in any environment, compared to needing to generate and store the same quantity of energy.
The closest tanks will come any time soon is a diesel-electric hybrid, for noise and electric load purposes (EW, lasers, etc).
Even moreso than cellphones.
Instead, for an eastern and central European countries, a war is the real threat. The chance to lose a war with Russia backed by China is very real.
And the reason it is real is the loss of protection from the US. It is no longer guaranteed that the US will participate once Russia invades, and that makes the invasion itself almost inevitable.
Participation of the US is important only because it has a massive stockpile of WMD. It is obvious for everyone that US is not prepared for a modern war on the ground against a real power.
Prosperity and economic growth doesn't really matter when you are threatened with losing the massive war with causalities calculated in millions.
You first want to secure and guarantee peace for the future, and then you think about economy, competition and so forth.
And massively increasing weapons production is the way to avoid the big war.
It's not like Germany is far away either. The Western edge of Ukraine is, in some places, closer to Berlin than the Western edge of Germany.
Not being able to trust US protection as much as in the past is evidently a terrible state of affairs, but this isn't the root of the problem.