There is a considerable amount of cultural distance between, say, one of the Cascadia cities (like Seattle), and Mississippi, and Boston, more so than you often find between different European countries. What deceives people is that Americans nominally all speak the same language despite the stark cultural and historical differences between regions.
My dad worked in nuclear, so I moved around a lot when I was a kid: Tricities Washington (sagebrush country), Toledo Ohio, Somewhere (Pennsville) New Jersey on the tristate border, Vicksburg Mississippi, and finally back to the PNW (Seattle). Actually, many Americans are fairly mobile, much more so than their European counterparts. Its not unusual to meet others like me who moved around a lot as kids (and are still moving, just not in the states anymore).
General American ignorance is quite a myth, though I'm sure their are many stationary Americans, there are just as many Americans who've lived everywhere.
People are fairly comfortable in most developed countries, they are in some way too stable: oppurtunities are provided, for sure, but the urge for mobility is not as strong as in the states. The states is very different, however: oppurtunities are not as numerous (economically segrated educational system), but the drive is much stronger to take them when presented because it sucks at the bottom.
I think this is a myth, and potentially a very dangerous one.
Asymmetric warfare only works when the side with greater symmetric power holds back due to other (political) concerns. If the US used full power in a total-war unrestrained sense, IEDs would be wholly irrelevant to the outcome. That's true even in a war using"just" unrestrained conventional weapons.
The lessons from Viet Nam, Iraq, Somalia, etc. are valuable for both sides in situations where there is no political will for unrestrained power, but don't make the mistake of believing that unrestrained power is forever off the table.
To me, at least, it seems like making that mistake in thought, on either side, virtually guarantees that it will some day come right back on the table, and with a vengeance.
There are people ignorant about the world in any country, I'm not sure why we always single out home bound Americans for being apathetic to world events. There is plenty of that to go around, even in Europe where people tend to travel more to other countries, but especially in China and even in Japan where people have many misconceptions about the rest of the world.
There are no more superpowers, not when IEDs are easy enough to procure by anyone.