Iran's missile assets may constrain US threat response

Analysis

Iran has a fairly well-developed indigenous capacity to produce missiles, with particular strength in anti-ship and ballistic designs. Technical help has come from North Korea in exchange for Iranian investment to bankroll the necessary research; China has also had input, and Iranian scientists have been adapting and improving Chinese designs.

Anti-ship missiles

The naval exercise earlier this week showcased two new assets:

• The Qader is a domestically produced system with a range of 200 kilometres, designed to be launched from either sea or land to hit large surface vessels. It is a sea-skimming missile, is not ballistic and cannot carry a nuclear warhead.
• The Noor missile is similar to the Qader: both are based on the Chinese C-802, although the Noor has a longer range. While the Noor in the latest case was launched from a ship, in the event of any hostilities in the Persian Gulf, Iran would most likely rely on its land-based missile assets.

Western naval vessels would have the defensive capabilities to cope with Iranian anti-ship missiles in a hypothetical engagement in open waters. However, the Strait of Hormuz is a different operating environment (see IRAN: Tehran will avoid blocking the Strait of Hormuz - December 30, 2011): missiles fired from shore-based batteries may be picked up late and counter-measures not deployed in time -- particularly if the target is operating close to land. Multiple launches may also overwhelm a ship's defences because of radar 'noise' from islands, fishing vessels, merchant ships and the like; these will degrade the performance of defensive radar systems.

The Qader's enhanced ability to skim the sea surface (at an altitude of 5-7 metres) would make it harder both to detect and down. This threat may even force the US Navy to operate its regional carrier battle group in the open waters of the Arabian Sea, rather than the tight confines of the Persian Gulf. The problem is that the farther away from its shores that Iranian missile defences can push any aircraft carrier, the less potent the carrier's air assets will be. Aircraft will have to attack from a longer range, which entails less time over targets and reduced ordnance payloads.

Ballistic missiles

Tehran has realised since the 1980s that its best means of national defence was to develop ballistic missiles. Its air force would be destroyed in fairly short order in any large-scale attack, making Iran reliant on a deterrence-based strategy. On the basis of the venerable Soviet Scud missile, Iran (which has not signed the Missile Technology Control Regime) has made significant strides in developing ballistic missiles over the last few decades, based on several factors:

1. Payload/range ratio

   The major balance inherent in any ballistic missile is the weight of warhead set against the range required. The lighter the warhead, the farther it can be delivered -- which explains Iran's drive for larger missiles and the development of multi-stage capabilities. Iran now operates the Ghadr two-stage missile, which is based on North Korea's Nodong.

2. Range

   The ability to build missiles with greater range will allow Tehran to base its missiles farther inland. As things stand, and with range limitations in mind, Iranian missiles are only a threat if they are based in the west of the country, near their potential targets. However, this would make them vulnerable to hypothetical pre-emptive strikes -- for example, by Israel (see ISRAEL/IRAN: Attack on nuclear assets unlikely soon - October 5, 2011). As greater range is added, missiles can be deployed farther east, beyond the range of Israeli aircraft.

3. Accuracy

   If a missile is highly accurate, its warhead need not be that large to achieve strategic effect. Hitting Bahrain might mean striking empty desert, or it might mean striking the largest US base in the region; the difference is all in the accuracy. Iran has problems here, because sophisticated guidance systems for ballistic missiles are not easily obtained or developed.

4. Survivability

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   Use of a solid-fuel propellant would make a pre-emptive strike much more difficult

   To be survivable against air attack, ballistic missiles need to be mobile (truck-mounted) -- but this means that US intelligence assets can normally pick up signs of any mobile Iranian ballistic missile being readied to fire. This is because they are liquid-fuelled, so any unit needs to be escorted by numerous back-up vehicles, which are visible as they move. The fuel also takes time to load, which implies time for adversaries to launch pre-emptive air strikes. For the Iranians, the answer would lie in the use of solid fuel, which is more stable and can be permanently held on board the missile.

Nuclear threat?

If Iran is to develop a viable nuclear deterrent, it needs not only to produce the actual weapon, but also to ensure that the associated missile is large enough to carry a nuclear device -- and likewise, the device itself must be small enough to be delivered. The complexity of these three inter-related technological advances explains why Tehran is unlikely to present a nuclear threat to its neighbours for years, if not decades, to come.

However, as its ballistic missiles increase in potency and survivability, the threat they pose will likewise increase. The longer a counter-strike is delayed, the more difficult success becomes. Faster preparation time and the development of missiles that can use solid fuel are thus the key variables that would constrain Western military operations against a hypothetical Iranian nuclear arsenal; fear of Tehran's capacity to develop either (or both) underwrites 'hair-trigger' thinking among some Western and Israeli military planners who advocate a strike on Iran sooner rather than later.