The men, who cannot be named, were convicted in October of gathering firearms, chemicals and bomb-making instructions, along with a mass of Islamist propaganda, for the attack on an unknown target.[break]
New South Wales Supreme Court´s Justice Anthony Whealy, who handed down the sentences at a purpose-built courthouse in Sydney´s west, said the plans were well advanced.
"There is no reason to doubt that, absent the intervention of the authorities, the plan might well have come to fruition in early 2006 or thereabouts," Whealy said.
The five were handed maximum terms of 23 to 28 years, with the shortest non-parole period being 17 years and three months. Four of the men are of Lebanese descent while the other is of Bangladeshi origin.
The court heard there was overwhelming evidence they wanted to create "at the very least, serious damage to property" and posed a "serious risk" to the public when they were arrested in 2005.
Australia´s former conservative government was closely aligned to the policies of former US president George W. Bush, and the country was one of the first to commit troops to the wars in Iraq and Afghanistan.
The five took Australia´s involvement in those conflicts as "acts of aggression against the wider Muslim community", prosecutor Richard Maidment told New South Wales Supreme Court earlier.
They spent months collecting chemicals, firearms and ammunition, and raids on their homes found "large quantities of literature which supported indiscriminate killing, mass murder and martyrdom in pursuit of violent jihad".
The men had pictures and videos showing the hijacked aircraft smashing into the World Trade Center in New York on September 11, 2001, as well as beheadings and death on the battlefield, Maidment said.
They also had documents glorifying Al-Qaeda chief Osama bin Laden and showing how to make a pipe-bomb with common ingredients such as citric acid and hair bleach, he said.
The court was shown more than 3,000 exhibits and heard from about 300 witnesses during the 10-month trial. However, the jury was spared being shown footage of hostages being executed by Muslim extremists.
"These were particularly distressing and graphic. It is impossible to imagine that any civilised person could watch these videos," Justice Whealy said.
"So disturbing were they, that none of the executions was shown to the jury."
Lawyers for the five had argued there were innocent explanations for much of the material and labelled the case "propagandist".
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