and you'd be right, gas diffuses quickly and even the amount that dissolves in the water will eventually off-gas. the NOx will be more of a local, acute problem. the nitric acid itself is worse. but still not nearly as bad as the East Palestine disaster. but the nitric acid will probably affect the local area for years, causing flora and fauna to die, and causing the drinking water for the local population to be an irritant and slightly toxic. nitric acid is hard to remove from water and amerika will not do it correctly

its not really that any one of these events is catastrophic. more that the cumulative effects of one event after another will lead to a continuous decrease in standard of living and life expectancy. and as the empire breaks down, these events will happen more often