I think that economy is really a subset of economic history. I don't know that economy questions would lose anything by being subsumed by economic history questions.
Merge of economic history into the economy tag has been completed
I'd actually argue (in fact did argue when the tag was created) that it should be the other way around. Everything on this site should by definition be history, so tacking "history" onto a lot of tags just increases the length of our tags without adding any useful information to them.