Updated

Give us our anti-missile laser cannon, say residents of an embattled Israeli border town.

Seventy residents of Sderot, a town of 20,000 people less than a mile from the Gaza Strip, sued Prime Minister Ehud Olmert and Defense Minister Ehud Barak Wednesday, demanding immediate deployment of the mothballed Nautilus missile-defense system.

The Nautilus system was jointly developed at a cost of $300 million by the U.S. and Israeli militaries to shoot down medium-range Katyusha rockets launched over the Lebanese border by Hezbollah.

• Click here for a video of the Nautilus system in action.

But it was deemed too expensive and too inaccurate, and both countries abandoned it in 2005.

Nautilus tests "shot down Katyushas, Qassams, and bombs with 100 percent success," countered Israeli lawyer Nitsana Darshan-Leitner in her lawsuit. "Israel could bring the system to Sderot and use it to protect the people there from Qassam rockets."

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Eleven Israelis, two Palestinians and one Chinese laborer have been killed since September 2000 by the roughly 6,500 Qassams launched by Islamic militants from the Gaza Strip.

The most recent fatality was on Feb. 27 in Sderot, whose residents flee to rocket shelters every time an alarm sounds.

Despite the claims made in the lawsuit, the Nautilus system needed several full-sized truck containers full of toxic chemicals to generate power, needed time to recharge for a second shot and had trouble getting its high-powered infrared beam through cloudy skies.

"Protecting the whole [northern] border of Israel would have required a few dozen of these systems," an Israeli military analyst told the New York Times in 2006. He pointed out that more than a couple of Katyushas in the air at once would have overwhelmed each unit.

The Nautilus was in fact never tested against the short-range Qassam rockets, which reach their targets within 10 seconds after launch, more quickly than most anti-missile systems can lock in on and intercept them.

Northrop Grumman claims it's improved the Nautilus system, now called SkyGuard, so that it's smaller and faster, though its press materials didn't specify a targeting-and-response time.

The Israeli military is in fact working on a different system called "Iron Dome," which essentially shoots down missiles with large bullets.

Though it will be able to shoot down the medium-range missiles Hamas began firing against the large coastal city of Ashkelon last month, it will be useless against the cheap, quick, highly inefficient Qassams.

Click here for a writeup on Wired.com, here for the plaintiffs' law firm's press release, here for a New York Times article on the Nautilus system and here for a Northrop Grumman description of SkyGuard.