This site – http://www.angelfire.com/nv/micronations/ – is a “collection of links to active websites concerning micronation, new country, new nation and homeland projects, as well as governments-in-exile, seditionist/independence movements and tribal sovereignty.” This page of it – http://www.angelfire.com/nv/micronations/real.html – lists “Actual Small Countries,” which is the most relevant to the OP. This Wikipeida article – http://en.wikipedia.org/wiki/Microstate – also covers such “microstates.”
According to the FAQ, they are “recognised by nations as an independent subject of international law,” but nowhere, AFAICT, do they refer to themselves as a country, state, or nation. Their two headquarters in Rome (see last question) have been granted extraterritoriality by Italy, so they do in fact have a very small territory over which they exercise sovereignty, and they issue stamps and coinage. The Grand Master of the Order resides at one of the headquarters, so they have a permanent population. No mention of passports that I can see, but it wouldn’t surprise me.
Monaco is only “semi-autonomous”.
The USA doesn’t recognize the Order of Malta AFAIK. It does have some nation-like authorities.
I’m not quite sure what you’re using to define this. It has full UN status, and a recent treaty guaranteed it would stay independent from France.
I am pretty sure it’s treaty with France doesn’t allow Monaco it’s own armed services, and France will defend it.
I don’t think it has full treaty powers with other nations, either.
The constitution of Monaco is fairly clear on the matter:
http://www.heraldica.org/topics/national/monaco.htm
Also this:
It’s not that Monaco ‘isn’t allowed’ its own military, but has agreed to another country taking the role of defense. If you regard this as removing its status as a country, you can cross Costa Rica and Iceland off the list, too.
What about Pitcairn Island? I know its area is larger than some of these places but surely it has the smallest population? (Except for Sealand, but I really don’t think that one counts.)
Looks like Pitcairn is still a UK territory:
http://www.cia.gov/cia/publications/factbook/geos/pc.html
It’s not an independent nation, but part of the overseas territory of the UK
According to this Straight Dope column, however, Sealand does satisfy the conditions under which many would consider it a “country,” though others say it’s “controversial.” I’m surprised that Cecil didn’t mention it as a case in point.
BTW, I heard that the real reason the future Prince of Sealand fired on those British sailors was that they were watching his sister sunbathe in the nude.