A few points:
1. The Nazis are misrepresented in American propaganda. They were a hugely popular regime domestically. The images of Secret Police disappearing people by night and a climate of fear and paranoia is far from the truth. Rather they fanatically rallied the German people, and actually had huge amounts of support in nations they conquered like France despite what the people there claim about their "resistance" after the fact.
In the end Allied troops faced the Volkssturm which was simply put the response of the common person in Germany. Young kids, old men and women, everyone literally picked up arms and threw themselves at the invading allies. While not as heavily publicized the things we did to stop this were simply put monsterous as that is what war is like. Groups like "The Hitler Youth" did not just vanish, nor did the massive public support the Nazi regime enjoyed.
Don't get me wrong, the Nazis did a lot of extremely evil things, but in general they were a group of highly popular economic reformists. Hitler himself was Time's "Man Of The Year" (if I recall the right magazine) based on his national policies, albeit this nomination had nothing to do with the Anti-Semitic Genocide or anything like that.
The thing is that a lot of people who invoke the image of "Nazis" are referring to a Hollywood image that never was. The Smithsonian has an entire section devoted to Allied propaganda during the war, and yeah... we demonized the Nazis pretty badly to make them easier to kill.
One thing connected to this is for example the "Human Skin Lampshades" which were tested and revealed to be goat skin. While it's acknowleged that there might be some nazi-crafted human flesh lampshades in undisclosed private collections, the ones avialible to the public and produced by the War Department were frauds intended to inspire hatred. The Nazis DID kill millions of Jews, but they did not flay them and use their skin for handcrafts.
2. When it comes to a militia, yes, there are ways that such things CAN go wrong which is why there is a system of balances. Where armed civilians balance the goverment, there are also things that the goverment has (or is supposed to have) for it's police forces to in turn keep them in line. Both exist and are supposed to play against each other.
The idea that anyone can become a cop, soldier, or even a general is part of it as well. Reducing the chances that the military can ever become a direct political tool, with say The President commanding the military to occupy the US under permanant martial law and round up all other sections (Congress, Senate, Supreme Court ) of the goverment. It also reduces the chance that a citizen-soldier is going to fire on civilians in his own country just because the goverment tells him to.
Of course with higher standards for the military (ie a smaller, more selective force) there is a problem as a definate caste is slowly developing with elitist practices and military families, that can erode that part of the equasion, but that is another discussion entirely.
Overall though the Nazis were not a whack job militia, they were a political party that rallied both the goverment of the time AND the people together. They also did not disarm the populance quite like has been suggesed above. Quite the contrary, especially in the final days of the war. Do some reading on the "Volkssturm" and what actually happened, though admittedly it's not exactly politically correct so hard information is hard to find, it doesn't play to our whole humanitarian vibe, and how the "greatest generation" were clean cut white knights beyond moral reproach. World War II was one of the dirtiest wars ever fought, it's just that unlike now we were smart enough to employ our own propaganda and information control and demonize our enemies while promoting ourselves, and effectively gagging alternative opinions by the media. Exactly the opposite of what we're doing in say Iraq.
We were "right" in World War II, but it's an academic point especially seeing as we won and got to write the history books. It was a very nasty affair.
3. America has the "Barbarians At the Gates" mentality because really we're the most enlightened culture to ever exist on planet earth, and even the best of the rest are at least a bit behind.
See, the thing is that America has a lot of problems, but most of the nations that do the criticizing are mono-ethnic, have extremely tight immigration, and/or for all apperances do not provide the degree of freedom that the US has to begin with.
For example France, one of our biggest critics, has very little in the way of empowered minorities (look at their Muslim riots and what set them off), it also has very tight immigration policies and standards for citizenship, it almost pulled out of the EU in the beginning because of the fear that it would be too easy for people from the rest of europe to move there and become French and draw French benefits. It also does not have a free press although it tries to present the illusion of one.
The same can be said of pretty much every nation out there. A lot of times we're receiving criticism for problems we are dealing with because of our tolerance and enlightenment. Sure we could lob like 99% of the minority groups over the border, and use "soft" discrimination tactics like some of the other nations that have minority populations do (as opposed to "hard" tactics for those that know the differance). Becoming more or less mono-ethnic with everyone fully adapted to the mainstream WOULD solve a lot of problems, and we could be just like a lot of our critics. But then we wouldn't be very bloody enlightened now would we?
In general the thing is that every culture out there wants to have itself be validated as "right" and "correct". To acknowledge that they are wrong about anything, can ultimatly put thousands of years worth of history and identity to question. Ignorance, solidarity, and convincing themselves that they are right, becomes a nessecity.
What's more most people on the planet more or less agree at least academically that humanity needs to be unified for it to survive. Space exploration is becoming a nessecity for living space if nothing else, never mind the need for resources irregardless of the expense of retreiving them to begin with (which is why so many nations are developing space programs or trying to), but it's not really practical with a divided planet for a lot of reasons (another whole discussion).
The thing is though that most people want to see THEIR culture be the one that everyone unites under. Viewed this way the USA's system is the only way to go. While many might not realize it if the French or Chinese or whatever were to take over and make everywhere France or China you'd see a single ethnicity dominating since the culture and ethnicity/nationality are the same. You'd wind up with a goodly portion of humanity as second class citizens.
China in paticular has a kind of eerie "master race" doctrine when you get down to it.
Of course the problem is that when things are presented this way, people from other nations who want their own history validated are likely to jump up and down and scream that what I'm saying is not true, and point out their accomplishments such as they are. The thing is though that we're looking at an overall situation and an accomplishment in one area without it happening with the full range of what we have done at the same time is ultimatly meaningless.
See for example, without a truely free press, and sizable minority populations, claiming that you've ended racism better than the US is just BS, since people don't exactly have room to bellyache to the mass societal consciousness (and they always will, over everything, racial or otherwise).
People naturally assume that when I refer to the US as being "the most enlightened" that I am portraying everyone else as facists or whatever, when that isn't the case. It's merely comparitive.
Also keep in mind that when I speak of the USA, I also refer to it's more or less direct Hegemony. While on paper seperate nations and in many cases vehement about it, I consider Pureto Rico, Canada, Samoa, etc.. to be extensions of the American culture/Hegemony to one extent or another.
As someone went off about before, Canada HAS made a lot of strides in civil liberties and is very close to the USA, but this is largely because of the USA. But despite how close things are there, there are still little issues like their gun control, and things like the abillity of their police to employ "blanket warrents" and effectively suspend the rights of their citizens (which I learned about in Criminal Justice classes a while ago).
I've been to Canada before (Niagra Falls specifically), for all intents and purposes it functions as an extension of the US. Arguably "little America" is the next best thing to America. Followed by the UK and Australia. Canada, America, and Australia all having come from the same English/British roots, and while people focus on the differances are alike in more ways than apart. As such, these cultures represent the most enlightened ones on the planet cumulatively and the best hope for humanity in general. Though admittedly there ARE degrees between them with America and it's Hegemony leading the pack.
