NYC was never a heavy industry town but there used to be a lot of small manufacturers. Famously the garment industry, but also all manner of odds and ends. All those factory lofts in lower Manhattan are still there, but converted to condos.
The big one will be if and when the New York Stock Exchange moves out. They have had disaster recovery plans in place since the Cold War, so they can do it quickly if need be.
Henry Repeating Arms fled to the United States from NY years ago.