One wordpress installation – Multiple domains (tlds)

It sounds like you should consider WordPress Multisite which lets you administer multiple sites from a single interface. Each site will have its own data within the database which isn’t exactly what you’re looking for, but at least then you could look at customizations per country. You could get started by replicating the appropriate tables so that content appears on the different TLDs.

If you try to use a single database for multiple domains you’ll run into problems with the setting(s) that tell WordPress what the site’s URL is which, in your case, would need multiple values rather than the single value that WordPress uses/expects.