OK. First of all, I doubt this is anything more than a bouncy...seriously, a Taiwanese student sponsored by a liberal? That might offend China.
That said, the reason the nameless kid was so silent may not have been shock and embarrassment, but rather fear of starting a liberal tirade while captive in a liberal's car. I've held my tongue in situations where there was no ready escape.
Who wants to hear a DU style rant for two hours in a car?