Many are still in denial about Western defense industrial production. This piece has a longer explanation, but here are a couple of paragraphs:
"GDP is but one measure of economic mass, and often a misleading one. For instance, except in extreme comparisons between the richest and poorest nations, GDP says little about the economic wellbeing and day-to-day quality of life of a regular person. It says even less about a country’s capacity to make war. Again, what matters in combat is the force that can be brought to bear and at the specific time and place it is needed. A similar logic applies to the production and distribution of armaments. In Western nations, GDP consists largely of things like professional services, real estate, and non-military government spending. In other words, collective GDP cannot be loaded into a howitzer and fired at the enemy.
The relationship between GDP and military power exists only to the extent a nation can turn wealth into weapons. The height of America’s ability to do this was during World War II, a conflict from which incorrectly-derived lessons continue to plague us. The US turned Detroit into a massive armaments factory, and did much the same throughout the rest of the country. Not only did the US have the factories at the time to do this, it also had the know-how. With the loss of domestic manufacturing came the disappearance of many of its necessary skill-sets. Then there are the supply-chain realities, which are just as stark. Those who claim the US could fight a war against China need to explain how the country could produce sufficient weapons and ammunition while also relying on its enemy for so many of the necessary material inputs. Then, of course, there is the question of how to pay for all of this."