Beyond that, theories vary, and the Northern California 9/11 Truth Alliance is showing films that explore the gamut during its seventh annual 9/11 Truth Film Festival happening this weekend.
"There are some people who are strongly opposed to what we're doing and some people who are deeply appreciative," says Northern California 9/11 Truth Alliance cofounder Carol Brouillet.
The festival already ran its first of two parts Thursday in Oakland, and the second half of the festival is set for Sunday at Herbst Theatre from 1 p.m. until after 9 p.m.Thursday's segment had about 300 attendees.
All attendees receive a questionnaire asking them about their beliefs regarding 9/11 before the festival, with options ranging from official -- that the attacks were planned and executed by Islamic terrorists and the government was unaware and unable to stop them -- to fringe beliefs that 9/11 was an inside job.
"Most [of our attendees] leaned toward the inside job but some believed the official narrative," Brouillet says.
The capstone film of Sunday evening is "9/11: Explosive Evidence -- Experts Speak Out," a 90-minute film by Architects and Engineers for 9/11 Truth. The film explores the notion that the collapsing of a smaller building near the Twin Towers was caused by explosives and that it may have been planned ahead of time -- findings that were dismissed in NIST's World Trade Center report.
Speakers also include the sister of a firefighter who died in the attacks. Brouillet said that although the films are promoting an alternate look at 9/11, "we're trying to be sensitive ... it's not like we don't feel the emotional pain also."
Tickets are $10 general, $7 seniors and students.