Could the US win a war with Iran?

From Blogo Maximo, a great Canadian blog by Steve Struthers, from London, Ontario. Please visit it.

Monday, March 20, 2006

The answer depends on what approach the US would take to destroy Iran's nuclear weapons program - an aerial bombardment, a ground war, or both.

Many analysts believe the US will use the same weapons it used in the initial salvo of the 2003 attack on Iraq: sub-launched Tomahawk missiles, and F117 stealth fighters dropping GBU-28 'bunker-buster' bombs.

Armed with conventional explosives alone, the GBU-28 cannot easily destroy bunkers located very deep underground. That lack is prompting the US to consider adding on 'mini-nukes', ranging from 0.3 to 300 kilotons (kT). To put things into perspective, consider that one kiloton of nuclear weapons energy equals roughly 1,000 tons of TNT. By comparison, the bombs used on Hiroshima and Nagasaki yielded 12 and 20 kilotons.

The US is portraying these tiny weapons as 'safe for civilians', in an attempt to make a nuclear attack on Iran somehow acceptable. The bombs will use kinetic energy to penetrate the bunkers, then detonate well below ground level. The resulting blast, heat and radiation are contained by the earth, thereby reducing civilian casualties.

Would these be enough, given the likely depth of the Iranian bunkers? To assess their possible effectiveness, one must first understand where they fit in the nuclear weapons hierarchy. Weapons yielding less than 2 kilotons, or Sub-Atomic Demolition Munitions, are used by military engineer units to deny bridges and roads to advancing enemy forces. SADMs have a limited effective radius and lack the power needed to destroy or damage deeply buried bunkers.

Bombs this small will detonate at ground level or just a few metres below and will kill or injure civilians by blast, heat, and immediate radiation. Prevailing winds will also carry the resulting fallout to non-target areas, causing still more deaths and acute radiation illness. While the deaths and casualties that would result would still be lower than would be the case if larger bombs are used, the 'mini nukes' are anything but 'safe for civilians'.

Larger bombs of 100kT or more would probably be enough to take out some of the deeper facilities. The Iranians have likely anticipated this risk by building their most important facilities much deeper underground. To really do the job, a bomb of around two megatons, yielding the equivalent of 2 million tons of TNT, is needed.

A two-megaton bomb will generate a crater 500 metres wide and 140 metres deep, enough to reach all but the very deepest bunkers. Unfortunately, a bomb that large is capable of destroying a major metropolitan centre and killing not just thousands of civilians, but potentially millions.

Given the obvious deficiencies of the mini-nukes, is the US telling the truth about the size of the bombs it plans to use? In the wake of a nuclear attack on Iran, actual bomb yield will be hotly debated by both sides. Post-attack rubble, fires and fallout will make getting at the truth even more difficult. For a while, at least. Since most of the targets are in or near urban areas, civilian casualties will be magnified as bombs miss their targets and buildings closest to the targets are imploded by seismic effects of the blasts.

The US has identified nearly 450 potential targets. Most of them could be neutralized, if bombs of sufficient size are used and high civilian casualties are considered an acceptable trade-off.

Then again, if victory is defined by bringing Iran's nuclear ambitions to a screeching halt, then yes, the US could easily win. In so doing it may lose the public relations battle it sought to win with its 'safe-for-civilians' nuclear bombs.

Winning a ground war seems somewhat less likely. Reliable information about the current strength of the Iranian Army is scant. It is believed that most of its ground forces inventory is obsolete or near obsolescent, with nearly 2,000 medium and main battle tanks, and several thousand wheeled fighting vehicles, artillery and anti-tank systems. All of which would pose a problem for US forces. As would the almost 800,000 regular and reserve ground troops Iran has, many of whom are battle-hardened from combat in the 1979-81 war with Iraq. A significant portion of Iran's terrain is rugged and mountainous, thereby posing additional hurdles to overcome.

Consider the 130,000 US troops now in Iraq. Recruiting efforts at home are not going well, forcing the US Army to desperately cling to every one of those troops any way it can. If they were diverted from Iraq to fight in Iran, there would be too few of them to do the job.

Military history shows that an attacker needs a three-to-one advantage over an enemy in order to win a battle. In practical terms, this means that the US Army would need a force some 2.4 million strong to gain that numerical advantage.

Conceivably, the US could win with a smaller force, bolstered by allied troops, air power, and superior weapons. In such a scenario, bigger questions remain. Could the US, with its national budget already being strained by the Iraq war, go on the total war footing required? Would Americans be willing to accept the WWII-style rationing and other privations imposed by such a war, which is likely to be protracted?

Moreover, since Iran lacks the capacity to physically attack the continental United States, what conditions would have to exist before America would enter into a ground war against Iran?

In my next article, I'll look at the myriad risks that a war with Iran would entail.