I think apathy overrides most of the benefits derived from rational discourse on the broader scale. In a limited forum such as HN, it's great.
When pushing the "the government is violating your rights and must be stopped" on a larger scale, factual precision becomes much less important.
The immediate goal is to generate as much general awareness and outrage as possible. Everything from the metadata vs content debate to service provider denials of data-sharing to Snowden's hot ex-girlfriend are distractions from that objective.
You speak as if rational discourse is useless to your objective (as noble as it may be).