Today's superpower would require over 2-million engineers/scientists yearly to cope with current military updates. Plus, the US'S production costs are overpriced and lethargic.. The US'S economy is leveraged to a single currency for both GDP and GNP performance. The US$ Dollar is just too strong and an enemy for low cost production and speed. Countries like N. Korea have a low cost and more reliable and disciplined workforce, free from drugs and obesity.
North Korea adopts another hypersonic weapon, outpacing anything US can field