Iran has several options, such as an all-out military offensive that likely would engulf the entire region, a more limited assault using proxies in Lebanon and the Gaza Strip, or a terrorism campaign against Israeli embassies and Jewish sites around the world.
What’s more, the counterstrike options entail global consequences, including a slowing in economic growth because of higher oil and gasoline prices, fuel shortages from shipping disruptions in the Persian Gulf and the potential for the U.S. to become embroiled in another war.
“Iran is going to have its own strategic dilemma after a strike,” said Matthew Kroenig, nuclear security fellow at the Council on Foreign Relations.
“On the one hand, it’s going to have to strike back to save face domestically and re-establish deterrence internationally. On the other hand, it’s not going to want to pick a fight with Israel or the United States that could lead to the destruction of the regime,” Mr. Kroenig said. “So it’s going to try to calibrate its response - do something, but not too much.”
Analysts agree that the scale and nature of Iran’s response will depend on many unpredictable factors, including the degree to which Tehran views Washington as having approved an Israeli strike.
The general assumption is that Iran would ask the Islamist militant groups Hamas in Gaza and Hezbollah in Lebanon to fire rockets at Israeli population centers. Tehran also probably would launch some of its own long-range Shahab-3 missiles while sponsoring terrorist attacks against Israeli embassies and Jewish soft targets around the world.
Analysts disagree, however, about whether Iran would act against U.S. interests and other third parties in the region, given that all-out retaliation could draw an overwhelming U.S. response and dampen international sympathy in the aftermath of an Israeli attack.
“In Iran, there is this belief and perception that U.S. and Israeli interests in the Middle East are almost identical and convergent, so if Israel attacks Iran, Tehran will believe that the U.S. gave Israel the green light,” said Alireza Nader, senior international policy analyst at the Rand Corp. and co-author of “Israel and Iran: A Dangerous Rivalry.”
But, he added: “All these things are very hard to tell because war doesn’t always go according to plan, and the situation could escalate out of control.”
Part of the difficulty in predicting Iranian retaliation is the number of options at the regime’s disposal.
Iran has threatened to close the Strait of Hormuz, through which about one-fifth of the world’s petroleum is transported. Economic forecasters predict that closing the strait could push the price of oil to more than $200 a barrel.
The Iranian regime also could sponsor attacks against U.S. forces in Afghanistan or strike U.S. assets in the Persian Gulf, such as the Navy’s 5th Fleet based in Bahrain. Alternatively, Tehran could attack U.S. allies in the Persian Gulf, many of which have been agitating for a strike against Iran.
Israel and Western nations suspect Iran of trying to build a nuclear weapon, which Tehran has denied. The Jewish state considers a nuclear-armed Iran an existential threat because of the regime’s call for Israel’s destruction.
The U.S. has urged Israel to allow international sanctions enough time to persuade Tehran’s leaders to change their behavior, but Israeli officials have said that the military should strike before Iran can secure its nuclear facilities from attack, presumably by this summer.
Suzanne Maloney, an Iran specialist at the Brookings Institution, said Tehran would “prefer to avoid a full-fledged confrontation with Washington,” but that the density of U.S. forces in the Persian Gulf would make it difficult for Tehran to do anything in the Gulf without drawing a U.S. response.
Equally hard to predict, analysts say, is how President Obama would react to each scenario, particularly if the crisis erupts in the heat of the fall’s presidential campaign, when he would face competing pressures to appear strong and to keep the inevitable spike in oil prices brief to avoid another recession.
“There’s a possibility that we would do nothing, aside from any immediate self-defense of any forces, because Obama would be very frustrated by such an Israeli decision and would want to underscore that it was not an American decision - and one way to prove that is to take a couple hits and don’t retaliate,” said Michael O’Hanlon, senior fellow at the Brookings Institution.
“Let’s say, for example, the Iranians fire a missile at a U.S. base in Kuwait and it lands smack in the middle of the desert, and shrapnel kills two Kuwaitis who work at the base and injures three American soldiers. That’s the kind of attack where I actually think that the president would have the option of doing nothing in reply.”
As reported by the New York Times, a war game held last month by U.S. Central Command to simulate the consequences of an Israeli strike imagined a different outcome, with an Iranian attack on a U.S. warship killing about 200 sailors and prompting the U.S. to launch follow-up strikes on the damaged nuclear facilities.
The war game posited that the initial Israeli strike would delay Iran’s nuclear program by a year and that the follow-up American strikes would set it back less than two more years.
Iran’s nuclear installations are dispersed throughout the country - some of them underground. Despite doubts about their capabilities to set back the Iranian nuclear program, Israeli officials maintain that the Jewish state has a credible military option.
Israeli Defense Minister Ehud Barak has said publicly that the costs of an Israeli strike - “maybe not even 500” dead Israeli civilians - would be worth the gains.
Others have been skeptical. Former Mossad chief Meir Dagan told CBS’ “60 Minutes” last month that a strike would ignite a “regional war” and would invite devastating missile strikes on the heart of Israel.
“It will be a devastating impact on our ability to continue with our daily life,” he said. “I think that Israel will be in a very serious situation for quite a time.”
Syria and Iranian dissidents
One wild card in the regional war, Mr. Dagan and others predict, is Syria.
Syrian President Bashar Assad, who is under domestic and international pressure to step down, possesses an arsenal of long-range M-600 and Scud missiles and, according to reports, one of the largest stockpiles of chemical and biological weapons in the Middle East.
“On the one hand, much of the regime’s legitimacy is wrapped up in resisting Israel,” said Andrew Tabler, senior fellow at the Washington Institute for Near East Policy. “On the other hand, Assad has his hands full and knows that going too far would bring about an Israeli counterstrike and could lead to the end of his regime, so I think it’s probable, though not certain, that he’ll stay out.”
Despite uncertainty over the actions of Iran and its allies, analysts say the Islamic republic would use a post-strike crisis to further crack down on the regime’s opposition.
“I think the day after the attack, there will be a state of emergency declared, the regime will round up anyone who it thinks might potentially be sympathetic to this attack,” said Abbas Milani, co-director of the Iran Democracy Project at the Hoover Institution.
“They have shown a knack for using these kinds of crises to absolutely, brutally suppress the domestic opposition and create the kind of atmosphere where their suppression is legitimized and the opposition is either co-opted or marginalized.”