This 2024 report from the Dallas Fed provides very clear evidence of the positive returns from past U.S. government research and development funding.

Total factor productivity is a noisy but generally accepted measure of the amount of GDP/productivity growth that is due to innovation rather than increases in inputs. Summary: The return CAUSED BY non-defense R&D spending is 140-210% over 8-12 years, which is higher than investments in infrastructure (which still provide a positive return) and defense R&D (NO CAUSAL EFFECT IDENTIFIED).

Since it’s noisy, maybe I would smooth it in the graph above, but nonetheless there is a very clear relationship between falling R&D spending and falling economic growth. Conversely, if you wanted to intentionally reduce growth and innovation in our economy, a good way to do that would be to reduce R&D spending. Another implication is that if R&D spending on weapons and war does NOT provide as great benefits, there is an opportunity cost to spending your R&D money on weapons and war rather than peaceful or at least dual-use technologies. So it’s pretty clear the actions of the current US administration (drastically cutting R&D spending and shifting it from civilian to military applications) do not match their stated intentions to boost economic growth.