Israel mulls military option for Iran nukes

That may help explain recent visits to Jerusalem by Mike McConnell, the U.S. director of national intelligence, and Adm. Michael Mullen, chairman of the Joint Chiefs of Staff, each of whom delivered a message to Israel that it does not have a green light to attack Iran at this time.

Senior Israeli officials, speaking on condition of anonymity because they do not wish to appear at odds with their most important ally, said they were concerned about a possible softening of the U.S. stance toward Iran.

Apparently to allay Israeli concerns, Bush administration officials last week assured visiting Israeli Defense Minister Ehud Barak that the U.S. has not ruled out the possibility of a military strike on Iran. And the U.S., aware of Israel's high anxiety over Iran's nukes, is also hooking Israel up to an advanced missile detection system known as X-Band to guard against any future attack by Iran, said a senior U.S. defense official, who spoke on condition of anonymity because the discussions over the issue have not been made public.

With sanctions and diplomacy still the international community's preferred method to get Iran to stop building the bomb, an Israeli strike does not appear imminent.

If it did attack, however, Israel would have to contend with upgraded Iranian defense capabilities, including 29 new Tor-M1 surface-to-air missile systems Iran purchased from Russia last year in a $700 million deal.

Russia has so far not gone through with a proposed sale to Iran of S-300 surface-to-air missiles, an even more powerful air defense system than the Tor-M1. An Israeli defense official said the deal is still on the table, however. This is a big source of consternation for Israel because the system could significantly complicate a pre-emptive Israeli assault on Iran.

Military experts say an Israeli strike would require manned aircraft to bombard multiple targets and heavy precision bombs that can blast through underground bunkers — something Israel failed to do in its 2006 war against Hezbollah. It's widely assumed that Israel is seeking to obtain bunker buster bombs, if it hasn't already done so.

Elite ground troops could also be necessary to penetrate the most difficult sites, though Israeli military planners say they see that option as perhaps too risky.

America's ability to take out Iran's nuclear facilities is far superior to Israel's.

Unlike Israel, the United States has cruise missiles that can deliver high-explosive bombs to precise locations and B-2 bombers capable of dropping 85 500-pound bombs in a single run.

Yet the cost of an attack — by the U.S., Israel or both — is likely to be enormous.

Iran could halt oil production and shut down tanker traffic in the strategic Strait of Hormuz, which could send the price of crude skyrocketing and wreck Western economies.

It could stir up trouble for the U.S. in Iraq by revving up Shiite militias there just as Washington is showing some important gains in reining in Iraqi chaos.

It could activate its militant proxies in both Lebanon and the Gaza Strip, from where Israel could come under heavy rocket attack. And it could strike Israel with its arsenal of Shahab-3 long-range missiles — something Israel is hoping to guard against through its Arrow missile defense system.

Perhaps most importantly, any strike on Iran — especially if it's done without having exhausted all diplomatic channels — could have the opposite of the desired effect, "actually increasing the nationalist fervor to build a nuclear weapon," said Meir Javedanfar, an Iranian-born Israeli and expert on Iranian affairs.

Whether an attack on Iran would be worth its cost would depend on how long the nuclear program could be delayed, said Chuck Freilich, a former Israeli deputy national security adviser and now a senior fellow at the Harvard Kennedy School.

"A two, three-year delay is not worth it. For a five to 10-year delay I would say yes," he said.

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