Shyness in anime and Japanese culture

So there's a girl who blushes at everything, feels self conscious about her uniform, has a crush on someone but is too afraid to talk, and when she hears a joke, she has a slightly embarassed look of flustered chagrin as her eyes squint and her cheeks raise, symbolized as ^^.  And she has a sweat drop on the back of her head.

Why?  In an age where modesty means nothing, why be shy at all?  A look at US voice actors in anime dubs will often have girls trying their hardest to imitate or act shy like their character, only to come off as overexaggerated.  And in the US, there's probably a lot less to be shy about.  Girls talk just like guys, know the same things, and can be just as outgoing.

>>13
Yummy.

>>22
You hit the nail mostly, but I'd like to add a few things regarding Comparative Sociological Systems.  The core of the matter is the social structure of both spheres.  Japan is an Eastern Asian nation, and has a Collectivist culture, as do many nations in the region.  In this regard, the opinion of the whole is prioritised over the opinion of the individual ("If this many people say I'm wrong I must be wrong.")  However, the United States is a Western ex-Frontier society, which has a heavy incidence of Individualistic culture.  ("It doesn't matter if everyone says I'm wrong, I know I am right because I know my situation best.")  In this regard, tactfulness in diplomacy can be seen as an attempt to interface with minimum risk of offending another.  Introversion becomes a very effect means of expressing mutual respect, nonaggression, and conformity with the demands of one's archetype.  This also extends from Japan's feudal heritage, where title, honor, and social status are highly regarded, thereby shaping the social interactions between individuals in the framework to be very formal and passive.