Sadly, for me at least, the humour is lacking mainly because, as you said, it's too accurate and when you do take a leap out of the box, it tends to be so far from the box that the box is no longer relevant as it should be (like the intro section for examples). You don't really make any jokes about the conspiracy theories and conspiracy theorists themselves, nor do you exhaust the possibilities for examining all the funnier permutations that could arise from such a situation occuring. You also don't make enough (funny) cultural observations and there is not enough SENSATIONALISM. Also you tend to make more subjective jokes (and I mean here one's that seem to be more a reflection of your own opinion than satirising the concept) like "Country Music" being banned, which might be funny if you were suggesting this - and justifying it - because of some observations on country music influencing separatist movements and regional identities and such, but I feel you just put that in a bit randomly as it is. There are some funny jokes, but they tend to be so separate from any kind of cohesive narrative that they just seem kind of pointless, regardless of their potential (the dissenter thing is quite good for example). The Amero section is far more like the kind of thing you want to do, less lists and more detailed hypothesis, this is the humour you need to go for. Unfortunately you carry this on too long, for the rest of the article basically, when it should really only be a small part of an overall insight into the U.S.E.
Right, the concept is neat enough and offers a lot of potential. First of all, I would suggest a better introduction, or at least one that makes clear what the article is going to be about, rather than jumping straight into the details. You need to make the connection between the reader's perception of reality (i.e. there is no active U.S.E, officially at least) and what you are going to suggest for the rest of the article. Say something along the lines of "The following outlines plans by XXXXX intended to bring into place one world government" or "The following is a hypothetical scenario...bla bla bla" or something (if this is to be hypothetical, if you are spinning it as a real country, approach the introduction in a more Encyclopaedic fashion, look at Wikipedia for an idea of this). But funnier (or more informative, or both). You see, it is necessary to do so because this concept exists somewhere in the realm between fantasy and reality, it is a twist of reality (so you could technically also approach it from a more obvious conspiracy theorist point of view) and is neither a satire on something that does exist or a satire on something that quite clearly doesn't exist - you must approach these articles carefully in order to make it easier (and funnier) for the reader. Having said all that, yours isn't such a bad example at all, it just needs to rearrange the first paragraph to make itself clearer (also the quote was a real turn-off for me and it took me a few sentences to recover), although I do feel it would be funnier if you approached it from a real sensationalist perspective (think "Daily Mail" "SHOCK! Proud Britons forced to share nation with negro types SHOCK!" type thing, except funnier), rather than stating it all as fact. So yes, the concept is good and offers plenty of potential but that potential is far from exhausted here.
Prose and formatting:
Could be far far more effective. Your writing isn't bad - at times it is very articulate - it's just you tend to skip from a formal to an extremely informal tone without any obvious reason (if you're going to do this to emphasise an American influence, I would recommend using italics or something, as you do with "fuck you", but then I don't think that line adds anything either but I'm not American, so a lot of this might be going straight over my head). The formatting is ok, but the order needs to be changed around a lot and I would actually suggest trying to imitate the design of a wikipedia page; make it clear and concise - Intro, History, Politics, Culture, Responses etc. - all under nice headings so it is clearer for the reader because at the moment it feels all over place, there is no uniting voice or angle you are approaching it from. Your spelling is pretty good though, so no problems there.
Well you have some images, but they're not funny (except the Amero, which is very good and I like the captions too), they're just 3 pictures of the earth saying "This is the U.S.E", more or less. When you reformat the actual article so that the text and flow is clearer, I would recommend tying one picture to each section that clarifies and reinforces for the reader what he is supposed to take from that particular section. For example in History, you could have 2 pictures - 1 of a government conference with a caption both informing the reader what is going on and making fun of it at the same time and a 2nd of some other detail you talk about in this section, maybe a street protest, some guerrilla action, or something. You must also here make fun of Americanisation more, you could have a pic in Culture that satirises the Americans trying to teach some obscure Amazonian tribe how to do something typically American (or if you can't have a pic, you could mention this kind of thing anyway).
Averaged. Just as an aside, if you did want to keep it more in the style you currently have, I would suggest moving it to something like "The United States of Earth Conspiracy" or something.
OK, so the concept has definite potential regardless of how you want to execute it. The only thing you need to do is make it clearer for the reader what is happening (and what has happened already). What is the country? Where did it come from? Who did it? How did it come about? When? etc.. etc.. Imagine all the questions someone might wonder while reading it and try and answer them within the article, rather than just glossing over a few details. Keep in things like the Amero, they are useful cultural aspects and also add far more of this kind of things. Use American stereotypes for humour and satirise it as the next step in a American globalisation campaign, considering all the implications this might have (and satirising them too) for other countries and cultures. Perhaps finish off with the brief observations of some Alien race that have popped by but are confused/disgusted by something quintessentially American and leave without introducing themselves. Turn the article into a narrative rather than a collection of unconnected paragraphs.