I wonder how a prolonged event Y, something with enough marketability to capture the public's eye for some time, might change opinions on the truth of proposition X. Something along the lines of the calculus, Gutenberg's printing press, the advent of manoeuvrable cannons, flintlocks, quantum mechanics, electric stoves (harnessed electricity), the concept of a national debt, etcetera.

I'd be interested in what if any effects the American National Security Agency scandal, or a worldwide marketing campaign by Finland advertising their healthcare system will or would have to this end.