I can’t find anything, but Cs-137 is used in food irradiation, so that’s a possibility.

And why exactly would they nuke the US? Do you think whoever wins the power struggle in Russia has a death wish or really wants to rule over a pile of radioactive rubble? The calculus of MAD isn’t going to change.

They may assassinate Trump in retaliation, but that just means everyone wins.

Nor does it comprehend the question. It just returned a statistically likely response to the prompt based on its training data.