This video is one of many crazy Rantings of Jared Lee Loughner, also known as classitup10 on YouTube. Notice his statement that the Beckinator is way cool?
In a series of videos, he gave a rambling account of obsessions and paranoias that appeared to be troubling him with increasing intensity up to the catastrophe. They included references to conscious dreaming, or "conscience dreaming" as he called it, a process of directing one's own dreams that he is thought to have practised. Another was a belief in the gold and silver standard of currency – a favourite topic of the rightwing of American politics that is regularly propounded by the Fox News commentator Glenn Beck.
The tone of Loughner's rantings is almost exclusively conservative and anti-government, with echoes of the populist campaigning of the Tea Party movement. "Don't trust the government listener!" he said in one video, accusing Washington of mind control and brainwashing.
The US constitution, the bible of the Tea Parties, features heavily, as does the suggestion that the federal government is acting against the text. "You don't have to accept the federalist laws. Read the United States of America constitution to apprehend all of the current treasonous laws."
There is also a strong streak of implicit violence in the postings.
He linked to his favourite video, America: Your Last Memory in a Terrorist Country, which shows a ghostly figure burning the US flag in the desert to a heavy metal song that repeatedly chants "Let the bodies hit the floor!"
He referred to people calling him a terrorist and wrote "a terrorist is a person who employs terror or terrorism, especially as a political weapon."
Until 4 October, Loughner was a student at Pima community college in Tucson, but he was suspended after a number of inappropriate acts.
The college said he had five contacts with the campus police for having disrupted classrooms and the library. In a YouTube video posted on 29 September, Loughner accused the college of fraud and of being illegal under the US constitution.
After Loughner quit the college, the institution made clear that, if he wished to return, he would have to undergo a mental health check to ensure that his presence did not "present a danger to himself or others".
Fellow students at Pima told local newspapers that he had displayed troubled behaviour. He was reported to be isolated and withdrawn and used to laugh out loud in the poetry class in a way that made others feel uneasy.
"He disrupted class frequently with nonsensical outbursts," Lynda Sorenson, who shared his mathematics class last year, told the Arizona Daily Star.
He lived with his parents on the northwest side of Tucson, a few miles away from the shooting scene. His difficulties began relatively early, with one incident recorded by police of a drug violation while he was at high school. He tried to enlist in the US military in Tucson but was turned away for unspecified reasons.
Arizona prides itself on its loose gun laws but there is still shock that a man with such a prolonged history of erratic and disturbing outbursts was able to legally acquire the gun he used in his rampage. The shootings were carried out with a Glock 19 semiautomatic, with a magazine of 30 bullets.