> I have also noticed that e.g. Lockheed Martin (maker of the F35) is not doing very well on the stock market.

There's no "e.g." here. It's only Lockmart, and it's because they recently lost the Next Generation Air Defense contract to Boeing. The rest of the US defense sector is fine (for now).

These statements from the US are more about keeping Europe dependent on the US (and thus the US keeping some geopolitical leverage) than about bolstering the US defense sector.