.com, .org, etc. and
country-specific ones like .us, .uk, .ca, etc.
The way that the ccTLDs is allocated is described in RFC 1591 and is mostly non-contentious, because the IANA has extremely limited discretion:
The IANA is not in the business of deciding what is and what is not a country. The selection of the ISO 3166 list as a basis for country code top-level domain names was made with the knowledge that ISO has a procedure for determining which entities should be and should not be on that list.
Naturally there's a fair bit of whining about this: Should Taiwan have a ccTLD? (it does). How about Palestine? Yep. Tibet? No. But since the IANA doesn't have any real discretion in this matter, it's not like the US is somehow imposing its preferences on the world through ICANN/IANA.
Of course, just knowing which domain names should exist doesn't
necessarily tell you who should get to control them. For
instance, there's was for a while some question about who should
be running Iraq's domain (.iq). In general, though, if you're
a national government in clear charge of your territory you're going
to get control of the ccTLD.
Incidentally, once the ccTLD is delegated, the country code manager has quite
wide discretion about what they do with it. Many countries (e.g., the UK, or Canada) do the expected thing and use it to allocate domains for
in-country users. Others, such as Tonga
just sell the domains as if they were .com.
Tuvalu
is particularly lucky in this regard, having been assigned the
country code .tv. Unsurprisingly, Tuvalu seems to
be treating this as mostly a money-making opportunity. Their registry
is run by VeriSign.
