i wanted to write a bit more (i'm the poster who wrote your daughter's right to be upset about nuclear weapons)- and I didn't want to seen unsympathetic or to write something that might make your daughter more upset, if she reads your posts.
I do think being upset about nuclear weapons is reasonable way to respond-because they are horrible things and we need to get rid of them. but I don't think nuclear war is something she needs to worry about right now. (Hopefully anyway)- but I don't.
One thing to point out to her,if she is wanting to store food etc- is to point out that if you felt the situation was that bad -you would be telling her, ' we need to store food' and that you would be telling her to help with boarding up windows etc.
Point out all the things as a parent you do to keep her safe-like making hold your hand to cross roads when she was little, having vaccinations , wearing a seat belt etc and how continually you do monitor safety in the family -like locking doors at night-and ask her to emotionally have a little rest for a bit- and trust you to be the first to say board up the windows if it even might be necessary, because that's what you'd do.
Say you are keeping an eye on things and ask her to allow her self to not worry , for a bit any way-if she can see you still happily watching tv and making tea etc, then maybe she can try to not worry so much.
You could combine this with saying, that in a more long term way,that if she is upset by the thought of nuclear weapons, that it's not the case that you need to either aim to not worry about them at all or feel terrified and distressed at the thought of them. There is a middle way, where you can acknowledge nuclear weapons are nasty and frightening, but you can learn about them and find what organizations are working against them,etc. And even do things on your own ,like write letters etc- and do something, to try and help work towards a world where don't have them, anymore, which would be better.
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