I am not actually sure why it's "the Netherlands". I suspect it's because "Netherlands" means "low countries", and countries is a common noun. In that light it could be similar to "The United States" or "The United Kingdom". Here you are referencing common nouns "state" and "kingdom", but proper nouns should not include an article such as "the". "The" implies "specific instance of" vs "a" which implies "any one of many". There are many "kingdoms", but we are talking about "United Kingdom", a very specific kingdom.
Long story short, I don't think it's just political, but based specific rules of the English grammar. Further reading:
Well, "Ukraine" probably means "the region" or "the border" or something like it, so the name sounds like something generic too that would need an article to disambiguate.
It really is politics, you can't be objectively correct here. It's just like me trying to convince you in accordance with my Mexican upbringing that America is not a country. I will not succeed, because the distinction is political. Since human languages are also consensus-based, grammar is in a sense also political (e.g. sociolinguistics).
By that logic we should all be saying "the England" because England is a "land". No, there is one objectively correct way of saying the name of a country (in English), and there are even explicit grammar rules for this specific instance. See the two pages I linked above.
Kind of related, in German we mostly say "die Ukraine" (the Ukraine", exactly the same as "the Netherlands" and surprisingly Slovakia (and former Czechoslovakia, but not always "the Czech Republic", only when we say "die Tschechische Republik", not "Tschechien" (which is informal, to be fair, as is "Slowakei" - but afaik "Tschechoslowakei" was official).
Did I confuse you already?
There's also "die Elfenbeinküste" (Ivory Coast), and certainly a few more.
Yes, you shouldn't do this. ;) In this case "Bein" (or in the long form "Gebein") is an outdated term for bone or skeleton.
"Elfenbein" is the modern word for ivory. The meaning of Elf is somewhat similar (though not identical) to English and therefore refers to the perceived beauty of ivory.
A tusk on the other hand is called "Stoßzahn" recognizing it as a tooth ("Zahn").
My German is not so great but bein means both leg and bone. I know that much. I just wasn't sure about the "elfen" part. So glad to see someone else provide some info on that bit.
FYI: Google translate is not the most reliable translator.
For the US, the full name is "The United States of America". In this name "State" isn't a common noun, it has a specific legal meaning identifying one of the 13 originally independent countries that joined together to form The United States of America. I'm not sure why they were never called countries, but that's essentially what they were, and to a limited extent they still function as small(ish) countries.
This is the same as saying "The European Union" rather than "European Union".
Long story short, I don't think it's just political, but based specific rules of the English grammar. Further reading:
http://time.com/12597/the-ukraine-or-ukraine/
http://en.wikipedia.org/wiki/Name_of_Ukraine