[Lurker]

There is no way a single nuke could possibly knock out even a majority of our critical infrastructure.

It would take several thermonuclear devices (hydrogen bombs) to accomplish that. While Iran may possess some standard fission type weapons and relatively short range tactical missiles there is no way they have the capability to do this.

The EMP threat from Iran is greatly exaggerated.

L

[datura]

It would take more than several warheads. A constellation of them would be more like it. But then again, HAARP would make it impossible for thier missiles to determine their altitude for detonation. (Atmosphere way early.)

[Habibi]

"There is no way a single nuke could possibly knock out even a majority of our critical infrastructure.
It would take several thermonuclear devices (hydrogen bombs) to accomplish that."

Perhaps the distinction between fusion and fission weapons is warranted. However, the threat of EMP is hardly limited to terrestrial assets. Low earth orbiting satellites are also at risk from such a detonation. While the loss of these LEO's would hardly be the end of civilization as we know it, it would be extremely expensive to replace them. Additionally, any nation could lob a nuke into space and eventually take out most of the LEO's in a few weeks.

The threat of EMP on electronics has been known for decades. It makes for some interesting reading.

http://www.fas.org/spp/starwars/congress/1997_h/h970716u.htm
http://www.physics.northwestern.edu/classes/2001Fall/Phyx135-2/19/emp.htm
http://huachuca-usaic.army.mil/contlearning/infrastructure/media/mipb/janmarch97/merkle.html
http://popularmechanics.com/science/military/2001/9/e-bomb/
http://www.airpower.maxwell.af.mil/airchronicles/kopp/apjemp.html
http://www.geocities.com/CapeCanaveral/5971/emp.html
http://www.georgetown.edu/sfs/programs/nssp/nssq/Edwards.pdf
http://www.its.bldrdoc.gov/fs-1037/dir-013/_1938.htm

[mewzilla]

The EMP threat from Iran is greatly exaggerated.

I just hope the mullahs know that :)

[Paul_Denton]

It would take several thermonuclear devices (hydrogen bombs) to accomplish that. While Iran may possess some standard fission type weapons and relatively short range tactical missiles there is no way they have the capability to do this.

Not only that you need very high yield bombs to even generate an EMP powerful enough just to neutralize an area. At the bare minimum you would need a 3 megaton device detonated at 200 miles (the US did such a test once, the Starfish test I belive) and even that only caused a power outtage for a few hours in Hawaii and New Zealand.