Disagree. Lean and JIT are designed to meet dynamic demand at high quality with low waste. US manufacturing never embraced Deming's work and that's why the US auto industry lost to the Japanese auto industry.

The US, especially the military, does not operate on lean nor JIT. They overproduce useless shit using Taylorist planning, they do not optimize production and thus cannot sustain producing critical but low-profit things - like protective gear - and they exhibit every single possible kind of waste described by the Lean/JIT regime.

Lean and JIT share some of the blame for US medical care woes, because they don't account for the massive demand surges that characterize viral exponential growth, something that doesn't really exist in the demand for automobiles and similar commodities.

The fact that no one is producing spare parts is all the evidence you need that Lean and JIT aren't anywhere near this problem.