Citizenship test in the US is administered after several years in the country. It's not like people are presented with it right off the plane. And they administer the test in several different languages too. Or at least they used to.
Truth be told, I think the Cit exam in the US is a joke. I'm not a huge fan of Life in the UK test either, but at least you read a book from which you're tested. In the US you get a list of like 30 questions from which they pick I think 10.
I think the problem of simplification in the test though is not just language-based. There's also the sheer amount of material that it's supposed to cover. The history, the government structure, some form of current affairs, how to copy sentences and read them out loud. Now take all that and reduce it to a 10-question test that probably needs to have a passage rate of 70%+ and we have a test that's the epitome of lowest common denominator.
ETA: vnicepeeps, I think I misrepresented the point of the chapter to which I was referring. He actually says that history text books tend to downplay the role of slavery in the North/South conflict, relegating it to some kind of secondary reason, when, according to the author, in reality it was the main reason -- the central issue over which the war was fought. And, according to him, it was recognized as such by people at the time. Everything else was a very distant second. That saying "North and South fought over slavery," is way more historically accurate than "there were a host of different reasons, one of them was slavery."
It's a funny issue to bring up, I think, because it shows the flip side of the Columbus issue: context run amok. To unambiguously say "it was about slavery first and foremost." is to admit the corollary: one side fought to end slavery, one side fought to keep it. To do so would be getting awfully close to actually making a judgement that North was on the side of the angels, and South..well..not so much. And those kinds of judgements make people verrrrry uncomfortable.