Why does the Philippine government have a filter on the internet? What are they hiding now?

First, this has nothing to do with President Gloria Macapagal-Arroyo as I have no interest in rehashing the sensitivity of her presidency. I fail to understand why in a democracy, that freedom of speech is filtered? (not talking about either as that is not my issue) Why can we not express opposing views via blog? Why do the Philippine people not march on Congress as if they can hold hearings on text messaging, then why not on the internet and allowing all people access to dissent?