There are about one hundred questions that would be relevant.
I don't know if the admins have tools to "mass retag" questions. Otherwise I could do it by hand a small batch at a time.
Certainly, that is something we could do. However, I think we must remember to avoid questions specific to Mathematica. There is a topic about it. As for mass tagging, I am not sure if it's possible. I would have to check on that one.
Anyway, I've created a tag so feel free to use it. I've been thinking whether to use
mathematica is just fine.