Embark on a two-hour drive heading northeast from Dominican Republic's blustering historical capital, past roadside villages and farmlands, and you'll find yourself in a place completely different from the one you just came from.

Such economic citizenship programmes, which are being run by several small island states in the region, have raised concerns that terrorists, criminals and other shady characters could buy Caribbean passports to evade justice, slip into Europe and North America through the back door, or squirrel away billions in stolen public money in tropical tax paradises.

The answer is all of them.