This explains in greater detail that this was no innocent SNAFU. It had been agreed in advance that the president's security detail would accompany him into the hall. You don't do s**t like this by accident. The Chileans were clearly trying to send a "message" but they got one sent right back at em'.
my take on all this FWIW is that Chile wants to be seen as a competent, developed country at the level of at least the lesser ones in Europe (e.g. - Greece, Portugal, someday Italy). things down here work pretty well and i think they have a good case, but not quite yet.
the APEC meeting to them "shows" that they "have arrived", and this went to their head. they are still playing out of their league, way out of their league, and proved it more than once during APEC.
worst, the Chileans down here don't see that they have done anything wrong (stoked up by the huge communist party and heavily infiltrated leftist anti-US press)