So, over in the thread Atomic War In The 80s, there was some discussion of EMP, which I think merits its own thread, as it's so often brought up in these sorts of threads. I've quoted a post by SergeantHeretic as an example of what gripes me, though I swear I'm not trying to pick on anyone). My responses/concerns are appended.
I am highly skeptical of the pooh-poohing of EMP. It isn't as if there haven't been instances where high-altitude EMP has caused significant damage. The damage caused would vary considerably depending on the size of the weapon, the altitude at which it was detonated, and its location relative to the Earth's magnetic field. For an example, I would direct you to the Soviets' Operation K tests in 1962, which did indeed cause considerable havoc:
This, and the Starfish Prime tests earlier that year, indeed suggest that a high-altitude EMP burst could be a significant problem for the targetted area. (An accurate understanding of the Starfish Prime test's effects is difficult to obtain partly because little was done contemporarily to assess its effects, and partly because the burst was so far from the affected area.) How significant a problem it would be is certainly debatable...but I think it's very difficult to sustain an argument that it wouldn't be a major problem or a problem at all.
By itself, a HAEMP wouldn't necessarily be crippling. But such a burst or bursts, combined with the havoc wrought by a full-on nuclear strike, would be crippling, both in the short and long term.
Here are a couple papers on the subject (I'll admit right now that a lot of the math went right over my head):
The Early-Time (E1) High-Altitude Electromagnetic Pulse (HEMP) and Its Impact on the U.S. Power Grid
A Russian Assessment of Several U.S.S.R. and U.S. HEMP Tests (PDF - see Page 33. There are also a couple interesting articles on battlefield nukes following, including the Pershing missile.)
No sir, it causes a short term interference with solid state electronics and that's all.
I am highly skeptical of the pooh-poohing of EMP. It isn't as if there haven't been instances where high-altitude EMP has caused significant damage. The damage caused would vary considerably depending on the size of the weapon, the altitude at which it was detonated, and its location relative to the Earth's magnetic field. For an example, I would direct you to the Soviets' Operation K tests in 1962, which did indeed cause considerable havoc:
The worst effects of a Russian high altitude test occurred on 22 October 1962 (during the Cuban missile crisis), in Operation K when a 300 kiloton missile-warhead detonated west of Dzhezkazgan (also called Zhezqazghan) at an altitude of 290 km (180 mi). The Soviet scientists instrumented a 570-kilometer (350 mi) section of telephone line in the area affected by the detonation in order to measure electromagnetic pulse effects.[2]
The EMP fused all of the 570-kilometer monitored overhead telephone line with measured currents of 1500 to 3400 amperes during the 22 October 1962 test.[3] The monitored telephone line was divided into sub-lines of 40 to 80 kilometers (about 25 to 50 miles) in length, separated by repeaters. Each sub-line was protected by fuses and by gas-filled overvoltage protectors. The EMP from the 22 October (K-3) nuclear test caused all of the fuses to blow and all of the overvoltage protectors to fire in all of the sub-lines of the 570 km telephone line.[2] The EMP from the same test started a fire that burned down the Karaganda power plant, and shut down 1,000 km (620 mi) of shallow-buried power cables between Astana (then called Aqmola) and Almaty.[3]
This, and the Starfish Prime tests earlier that year, indeed suggest that a high-altitude EMP burst could be a significant problem for the targetted area. (An accurate understanding of the Starfish Prime test's effects is difficult to obtain partly because little was done contemporarily to assess its effects, and partly because the burst was so far from the affected area.) How significant a problem it would be is certainly debatable...but I think it's very difficult to sustain an argument that it wouldn't be a major problem or a problem at all.
By itself, a HAEMP wouldn't necessarily be crippling. But such a burst or bursts, combined with the havoc wrought by a full-on nuclear strike, would be crippling, both in the short and long term.
Here are a couple papers on the subject (I'll admit right now that a lot of the math went right over my head):
The Early-Time (E1) High-Altitude Electromagnetic Pulse (HEMP) and Its Impact on the U.S. Power Grid
A Russian Assessment of Several U.S.S.R. and U.S. HEMP Tests (PDF - see Page 33. There are also a couple interesting articles on battlefield nukes following, including the Pershing missile.)