TEL AVIV, Israel - One might call it the Armageddon scenario: a massive and coordinated missile attack on Israel from many fronts.

As the rockets rain down, only the United States can save a nation from annihilation.

And they have been warning about it long enough. Now, at last, the direst predictions will be played out.

Now for the good news.

Almost all of this will take place within the safe confines of computerized simulation for three weeks starting next week. 

There is no war, merely the preparation for one, and the Middle East is a place where it pays off to be prepared.

Israeli-American Operation Austere Challenge will not be cheap. The biggest ever joint Israeli-American drill of its type to be conducted throughout Israel and off-shore by the two sides comes with a combined bill of close to $40 million.

According to the U.S. Department of Defense, the U.S. has pledged $30 million to the exercise and the Israelis estimated their exercise costs at 30 million shekels -- around $7.9 million.

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The drill will involve some 3,500 U.S. personnel, with around 1,000 troops deployed in theater, along with a navy cruiser to serve as the control center, and Patriot missile defense batteries.

Together the two sides will find out if their command systems and computer codes are compatible.

But if much of the exercise will take place in the virtual world, there’s an all too real world backdrop, which is proving tricky for the military to maneuver around.

"This exercise is purely about improving combined U.S.-Israeli military capability,’’ U.S. Air Force Lt. Gen. Craig Franklin, told reporters this week.

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"It is not related to any national elections nor any perceived tensions in the Middle East,’’ he added.

But, like it or not, this is a drill taking place in the heat of two general election campaigns and during what is surely only a lull in hostilities over Iran.

Austere Challenge has been delayed  and scaled back since the height of Israeli saber-rattling had Gen. Martin Dempsey, chairman of the Joint Cheifs of Staff, saying he did not want America to be seen as "complicit" in an Israeli attack.

Both sides have denied that changes to the drill are related to this very public disagreement, and last month, Israeli Prime Minister Benjamin Netanyahu pushed back his deadline to halt Tehran’s nuclear program to next summer.

Still, it’s a conflict delayed, not averted.

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In the meantime, Netanyahu has turned his attentions to fighting for re-election. He wants Iran and Israel’s security to figure as the big issues.

Austere Challenge allows him the chance to re-assure worried voters he’s back on side with their most important ally.

Of course, that’s not a bad message for President Barack Obama to be sending out too, with his own electoral destiny rather closer to hand, and facing Mitt Romney’s charge of "throwing Israel under the bus.’’

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In military terms, the generals told NBC News this week they will count Austere Challenge a success if they manage to stop any simulated missiles striking Israeli soil.

Political leaders on both sides are hoping for a similar level of protection from their rivals’ rhetorical rockets. 

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