At first blush, the US government's case against the Arizona's "Viper Militia" - accusing members of plotting to destroy government buildings - seemed as overpowering as a sightseer's initial gaze into the Grand Canyon.
During an early-morning raid on July 1, agents conducted a sweep of Phoenix-area homes, arresting 13 suspected militia members and confiscating a deadly cache of materiel that officials believed was intended to be used to blow up at least seven federal buildings here.
But events since that raid have cast doubt on just how solid the government's case against the Vipers is.
The huge amount of weapons taken into custody leaves little doubt that the group was partaking in violent activities. What is in question is how they were planning to use their massive firepower and if their plans involved a conspiracy against the government.
The 12 arrested members of the Viper Militia - one was released after being taken into custody - have been charged with conspiracy to unlawfully manufacture, receive, and possess destructive devices. Some also face charges of unlawfully possessing guns.
But in last week's detention hearings, an Alcohol, Tobacco and Firearms agent acknowledged that he had no evidence of an impending bomb plot.
That prompted Janet Napolitano, US attorney for Arizona, to apologize for misleading the public in earlier statements about the Vipers' "organized plan" of civil disorder and their intentions of training "militia members in the destruction of federal buildings."
Central to the federal government's case are two confiscated video tapes - one that shows members detonating bombs and the other that allegedly shows Viper members spelling out how to collapse targeted buildings and disrupt utilities. The first video tape was shown in court last week. The second was not.
Defense attorneys discount that militia members were a part of the destructive plan. "There was no such plot," says defense attorney Deborah Williams. "The only thing we've seen blown up on film was a hunk of dirt."
But Assistant US Attorney Frederick Battista maintains the militia members are dangerous. "They had the tape, they had the training, and they had the capability," he says.
A judge ordered six militia members released to await trial, requiring them to wear electronic ankle bracelets to monitor their movements. The other six will continue to be held in jail until the Aug. 20 trial, because the judge in the case said they posed a danger to the country.
An ATF agent says his agency took pains at the outset to avoid asserting that a terrorist attack was imminent. Ms. Napolitano, meanwhile, says additional charges may be pending.