We won’t. Western leaders won’t do jack shit. Even if it makes a major city an irradiated wasteland for the next 100 years.
A “dirty bomb” won’t / can’t make a city an irradiated wasteland. It cause destruction from the explosion. And it will spread whatever radioactivity (contamination ) is contained in the device.
Contaminated areas can be cleaned, and yes I would volunteer to assist in that. The levels of radioactivity we are talking about here are, relatively speaking, minor.
The BIGGEST impact is fear induced in the public.