Sometime next week, an Iranian delegation will arrive in Moscow and sign a contract to purchase the S-300, one of the world’s most advanced air defense systems.  Tehran has long sought the S-300, and came close to acquiring it in 2010, cancelling the deal at the last moment due to American pressure.

Flash forward five years.  With the recently-concluded nuclear agreement between the U.S. and Iran (and the end of economic sanctions), Moscow and its friends in Tehran are ready to do business.  And with upwards of $150 billion flowing to the mullahs, Iran will have ample funds for a variety of political and military projects.  More ballistic missiles with better accuracy?  Check.  Squadrons of new aircraft for the IRGC Air Force?  Ditto.  More assistance for Hizballah.  You bet.  And a state-of-the-art defense system to protect Iran’s nuclear site?  The timing of Tehran’s announcement is a reflection of the priority assigned to the S-300.

Details from Reuters:

“The text of the contract is ready and our friends will go to Russia next week to sign the contract,” Defense Minister Hossein Dehghan was quoted as saying by the Fars news agency.
Dehghan said Iran had initially planned to acquire three “battalions” of S-300 launchers, but had since increased its order to four.

He did not specify how many missile launchers would be in each battalion, a standard military grouping whose size can vary depending on nationality, equipment and role.

No timetable for delivery of the S-300 has been announced.  Traditionally, Russia has delivered the surface-to-air missile system to its customers by ship, usually through ports in the Black Sea region.  But S-300 components are air transportable (and with Iran in an obvious hurry to acquire the system), it would not be surprising to see Russian transports flying radars, launchers and support equipment to locations in Iran.  And, with support by contractors from Russia, the Iranians could achieve an initial operating capability in a matter of days.  

While acquisition of the S-300 was delayed for years, Iran has never stopped preparing for arrival of the system.  Approximately three years ago, the Times of Israel reported that Tehran was building a massive air defense training and support facility in southern Iran.  

The new base, located near the city of Abadeh, in southern Iran, will cost $300 million, be home to 6,000 personnel, and host seven battalions, Iran’s Fars news agency reported Tuesday.

The Deputy Commander of the Khatam ol-Anbia Air Defense Base, Mohammad Hosseini, said the base, the largest of its kind in Iran, will also include one of the most important military training centers in the country.

Last month, a senior Iranian air defense commander asserted that all Iranian air defense units and systems are fully prepared to repel possible enemy air raids.

As we noted at the time, Iran already had a fully-developed infrastructure for its aging, American-built I-HAWK SAM system, acquired in the 1970s.  With the I-HAWK at the end of its operational life, it made no sense to invest so heavily in a new base for that system.  On the other hand, delivery of the S-300 would require construction of a new training and maintenance complex.  Presumably, the Abadeh complex is now finished (or nearing completion) and would be available to support the S-300.  

Obviously, news of the S-300 deal has ominous implications for Israel.  Deployment of a modern, mobile SAM system would greatly complicate any IAF strike against Iran’s nuclear facilities.  As we’ve noted in the past, any long-distance Israeli raid would be asset limit, simply because the IAF has only a handful on aerial tankers to support the mission:  

“..With only seven KC-707s in the Israeli inventory (and no more than 4-5 dedicated to the Iran mission), the size of the strike package is limited by the number of fighter aircraft that could be supported by the tankers.  Various estimates put the number of F-15s and F-16s at somewhere between 24 and 42.  However, not all of those aircraft will be putting bombs on target; at least some of the Eagles will be assigned to offensive counter-air missions, performing fighter sweeps ahead of the strikers, to ensure that hostile fighters do not interfere with strike aircraft.  

But Israel may have other options that would preclude a round-robin, non-stop bombing mission.  Some sources suggest that Saudi Arabia might be willing to let the IAF utilize some of its installations as a post-strike refueling stop.  That would reduce tanker support requirements and allow the Israelis to dispatch more attack aircraft, but there are no assurances such a deal has been reached, and cooperation with Jerusalem would come at a high cost for the Saudi government.  Still, given the alternative (a nuclear-armed Iran), Riyadh may decide the risk is worth taking.

Another–and more likely–forward basing option is located north of Iran, in Azerbaijan.  Relations between Jerusalem and Baku have grown close in recent years; Israel is a key customer for Azeri oil exports and the IDF has helped Azerbaijan upgrade its military forces and provides critical intelligence information on Iran.  The Baku government has long been suspicious of Tehran, accusing the Iranians of trying to inflame Azerbaijan’s Shia majority, who live under one of the few remaining secular governments in the Islamic world.  Almost three years ago, we noted the growing relationship between Israel and Azerbaijan, and most experts agreed that Baku would have no problem with Israel using its bases to support a strike against Iran, provided the IAF presence was limited and not widely publicized.”

How does the S-300 change that equation?  For starters, the IAF would have to dedicate more airframes to the SEAD (suppression of enemy air defenses) role.  Hanging more anti-radiation missiles on the jets would mean fewer bombs on target, even if some of the aircraft are preforming multiple roles.  You don’t need to be a weapons school grad to understand that the probabilities of damaging or destroying an underground facility are decreased as the bomb count declines. Meanwhile, the odds of losing aircraft and crews increase significantly once the S-300 becomes operational.  

But that does not mean the new SAM system would completely deter an Israeli attack.  The IAF is very familiar with the S-300.  Along with detailed technical knowledge of the air defense system, Israeli pilots have actually flown against operational versions of the S-300, most prominently during a joint 2013 exercise with the Hellenic Air Force.  The same drill also provided opportunities for IAF crews to practice the long-range navigation and in-flight refueling skills required for a raid against Iran.  

Clearly, the Israelis would prefer to strike Iranian nuclear facilities before the S-300 arrives in-country.  But the window for such an attack is closing, and closing rapidly.  Even an advanced military like the IDF would need a few weeks to prepare and possibly pre-deploy forces to locations like Azeribaijan or the Kurdish region of northern Iraq.  Meanwhile, the clock is ticking down to the arrival of that first IL-76 or AN-124 and delivery of the first launchers, command vehicles and radars.  

The next couple of months should be very interesting in the Persian Gulf.  

Under terms of the catastrophic U.S.-Iran nuclear deal, we are “obligated” to help protect Tehran’s nuclear facilities from sabatoge.  But officially, that guarantee does not extend to defending the nuclear sites from air attack.  Earlier this year, President Obama threatened to shoot down Israeli warplanes transiting through Iraqi airspace to attack Iran.  Those promises brought a collective yawn from Israel’s military and political leadership; as they have demonstrated on numerous occasions, the Israelis are masters of tactical deception, and quite capable of getting a strike package into Iran without our knowledge.  Of course, the same tactics could–and would–be used against the Iranian air defense network.  That underscores the fact that a raid against targets defended by the S-300 wouldn’t be mission impossible–just a mission that would be much more complex, and carry greater risks.