Why Don't we Have a .bank?

Why don’t we have a .bank or .bank.country_code TLD that’s regulated by the same people that regulate the banks themselves? Most countries, with the notable exception of the US (which has multiple National regulators and a second tier of State ones), have a single body regulating all the banks so why not use their established trust metrics (you must be at least this tall to be a bank) to determine who can have a .bank domain?

In additional to helping people find their bank online (although if they can’t find it should they be doing online account management?) it’d help prevent a lot of phishing. I like the idea of a decentralised model (which would have the benefit of local knowledge) rather than a single globe spanning group but decentralisation does seem more likely to end up having a very weak link in some small, “legally interesting” country.