Iran more than tripled its arsenal of Shahab-3 intermediate-range ballistic missiles (IRBMs) in 2008, Western intelligence sources have said, in a sign that the country is preparing for a prolonged conflict.
"At the beginning of 2008 [Iran] had about 30 operational missiles compared with more than 100 missiles today," an intelligence source told Jane's.
With the Israelis and US strengthening Israeli missile defenses, it is only natural that to maintain deterence the Iranians would build up their forces as fast as possible. Also, from the perspective of Iran, it is essential that in the event of war it be able to inflict some form of damage to counter that inflicted by more powerful aggressors. Thus a crash system to build more Shahabs makes sense, from a defensive posture.