# Electromagnetic pulse attack question? **URL:** \ **Category:** Factual Questions\ **Created:** [March 20, 2018, 12:46pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879 "2018-03-20T12:46:17Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Mr\_Quatro](https://avatars.discourse-cdn.com/v4/letter/m/bc8723/32.png) [@Mr\_Quatro](https://boards.straightdope.com/u/Mr_Quatro)\ **Post date:** [March 20, 2018, 12:46pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/1 "2018-03-20T12:46:17Z")
Would a submarine survive an EMP strike if it was submerged? > **[Security expert warns legislative committee of dangers of EMP attack](https://www.carolinajournal.com/security-expert-warns-legislative-committee-of-dangers-of-emp-attack/)** > > Peter Vincent Pry — executive director of the task force on National and Homeland Security — is on a mission to educate people about the dangers of an electromagnetic pulse attack. Pry’s recent stop on his educational tour was the Joint Legislative... Peter Vincent Pry — executive director of the task force on National and Homeland Security > [@](#): > > The threat is very real, he said. > > EMPs are bursts of electromagnetic energy which can disrupt or seriously damage electronic equipment. These bursts are not visible to the naked eye and don’t cause physical damage to people, but they can wreak havoc on an electric grid. > > “It has so much energy when it couples into electronics it will destroy them,” Pry said. > > An EMP burst could cause a widespread, protracted blackout and bring the United States to a standstill if it hit the right target. Pry said if an EMP burst hit a major civilian electric grids then anything that requires electricity would be shut down. > > “We estimate that a nationwide blackout that last a year could kill up to 90 percent of our population through starvation, disease, and societal collapse,” ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [March 20, 2018, 12:54pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/2 "2018-03-20T12:54:07Z")
Radio waves don’t travel well underwater, and the military uses electronic equipment that is “hardened” against EMPs, so I’d say yes in deep water. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [March 20, 2018, 1:06pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/3 "2018-03-20T13:06:49Z")
Of course, any question like this depends on the details of the EMP attack, and in this case on the details of the submersion. There are EMP weapons designed to take out individual cars (they don’t work very well, but that’s what they’re designed for), and there are EMP weapons that consist of powerful nukes that are meant to affect an entire continent, and a sub could be under a couple of meters of water, or a kilometer. That said, I have no idea what the relevance is of a power outage that lasts a year. The only way we’d get that would be if someone or something repeatedly pulsed us every few days, as soon as we got the systems back up. ---
**Author:** ![Mr\_Quatro](https://avatars.discourse-cdn.com/v4/letter/m/bc8723/32.png) [@Mr\_Quatro](https://boards.straightdope.com/u/Mr_Quatro)\ **Post date:** [March 20, 2018, 1:16pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/4 "2018-03-20T13:16:06Z")
> [@Chronos](#): > > That said, I have no idea what the relevance is of a power outage that lasts a year. The only way we’d get that would be if someone or something repeatedly pulsed us every few days, as soon as we got the systems back up. Probably based on a nuclear attack which would not target just one area like Washington DC, but the entire east coast, Colorado, Missouri, North Dakota, Montana, Idaho and Washington State. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [March 20, 2018, 1:37pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/5 "2018-03-20T13:37:59Z")
A blackout lasting a year with a 90 percent death rate and societal collapse kinda requires everyone to be a helpless idiot. People aren’t that helpless and stupid. And if we’re using nukes (which is pretty much the only way you’re going to get that level of EMP damage), you might as well actually be nuking cities instead of just targeting the nation’s electrical grid. That said, hardening the U.S. electrical infrastructure is a good idea. I suspect that Peter Vincent Pry is doing a bit of scaremongering to try to get funding to do that, as anything less than scaremongering probably isn’t going to convince Congress to shell out a few billion dollars to do the work. As for the submarine, as **Chronos** said, the depth matters. An EMP wouldn’t have much of an effect on a deep sub for the same reason that the deep sub can’t communicate via radio. Water does a good job of blocking electromagnetic waves. If the sub is on the surface or close to it, like it’s snorkeling or snooping around at periscope depth, or maybe it has come to the surface to communicate to a satellite, then the sub could be in big trouble. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [March 20, 2018, 2:08pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/6 "2018-03-20T14:08:00Z")
The length of the conductor exposed to EMP matters. Cross-country transmission lines will develop very large voltages that can fry whatever is plugged into outlets. But [according to Wikipedia,](https://en.wikipedia.org/wiki/Nuclear_electromagnetic_pulse#On_cars) small items that aren’t plugged in have a much lower risk of being damaged. Cars are a relevant example, in that they are short, tend to have metal paneling, and typically already include shielding to cope with EMI from the spark plugs (fun fact: in the [US National Radio Quiet Zone,](https://en.wikipedia.org/wiki/United_States_National_Radio_Quiet_Zone) vehicles with spark-ignited engines are not allowed because the spark noise interferes with radio wave research, including astronomy). So a submarine, with a nearly-contiguous steel hull only a few hundred feet long, with a design that probably includes defenses against EMP, submerged several hundred feet below the surface in nice salty sea water, will probably be OK. ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [March 20, 2018, 3:06pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/7 "2018-03-20T15:06:29Z")
[EMP panic seems to be all Dr. Fry thinks about](https://www.amazon.com/Dr.-Peter-Vincent-Pry/e/B00IUMVT0A). ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 20, 2018, 3:44pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/8 "2018-03-20T15:44:16Z")
> [@engineer\_comp\_geek](#): > > People aren’t that helpless and stupid. I admire your optimism. Let’s take a look at Katrina, which was a very localized event involving one city, New Orleans. Social order pretty much collapsed. There were literally bands of roving people with guns and virtually no real help for days. All this happened with every other part of the United States in perfect order. Now expand this to a scenario involving dozens of cities and the nation as a whole in complete chaos. I do believe, however, that people in rural areas would fare much better. > [@engineer\_comp\_geek](#): > > And if we’re using nukes (which is pretty much the only way you’re going to get that level of EMP damage), you might as well actually be nuking cities instead of just targeting the nation’s electrical grid. I disagree. If I’m an aggressor, I want chaos to be an ongoing weapon in my favor. Setting off several 100 megaton devices in key locations and completely crippling power and communications over thousands of miles will produce panic and chaos above and beyond the actual bomb destruction at ground level. When we attacked Iraq, our first wave of jets were stealth aircraft that destroyed radar and communications targets, not military targets. ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [March 20, 2018, 3:48pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/9 "2018-03-20T15:48:49Z")
Of course setting off several 100 megaton devices in key locations will set off mass panic…but it will be because of the massive death toll and spreading radiation, and not to a fictional “year without electricity”. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [March 20, 2018, 3:58pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/10 "2018-03-20T15:58:51Z")
Yes, once society breaks down, it takes a long time to rebuild it. But society doesn’t break down immediately whenever there’s a power outage. Some places have had widespread power outages from [events very much like an EMP](https://www.nasa.gov/topics/earth/features/sun_darkness.html), and the power was out for only twelve hours before it was brought back up. Other places have had power outages lasting for several days, and emerged with society intact. So there’s plenty of time to fix an EMP before it becomes serious. Now, if we’re talking about war, there are a few nations who could EMP the entire US (Russia and China are the only ones of those whom we could plausibly end up at war with, but Britain or France _might_ be able to do it, too). But there’s nobody who could _repeatedly_ EMP us. The only way to EMP an entire continent is via nukes, which would mean that within half an hour after the attack, the attacking country would be in no shape to do anything further to us. Now, there might still be panic and rioting and so on from the fact that HOLY SHIT WE JUST GOT NUKED, but the power outages that could be fixed in a few days would be the least of our concerns. ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [March 20, 2018, 4:04pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/11 "2018-03-20T16:04:14Z")
> [@Chronos](#): > > … > Now, if we’re talking about war, there are a few nations who could EMP the entire US (Russia and China are the only ones of those whom we could plausibly end up at war with, but Britain or France _might_ be able to do it, too)… Damn. Now I have one thing more to worry about the [Big Milkshake](https://en.wikipedia.org/wiki/Force_de_dissuasion). ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [March 22, 2018, 5:56am UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/12 "2018-03-22T05:56:00Z")
> [@Jasmine](#): > > I disagree. If I’m an aggressor, I want chaos to be an ongoing weapon in my favor. Setting off several 100 megaton devices in key locations and completely crippling power and communications over thousands of miles will produce panic and chaos above and beyond the actual bomb destruction at ground level. It’s also set off chaos and panic when a thousand or so American nuclear weapons fry the aggressor’s country. A nuclear attack on the US is a suicide attack; the aggressor’s nation will very quickly no longer exist in a meaningful fashion. Therefore there’s no reason to hold back with something as mild as an EMP strike. ---
**Author:** ![Lord\_Feldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lord_feldon/32/341_2.png) [@Lord\_Feldon](https://boards.straightdope.com/u/Lord_Feldon)\ **Post date:** [March 22, 2018, 6:24am UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/13 "2018-03-22T06:24:45Z")
> [@Czarcasm](#): > > [EMP panic seems to be all Dr. Fry thinks about](https://www.amazon.com/Dr.-Peter-Vincent-Pry/e/B00IUMVT0A). He’s the head of a think tank that does nothing but scaremonger about EMPs. (The “Task Force on National and Homeland Security” is not a government body.) I cannot find any record of the major donors to his task force, but I have some guesses. ---
**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\ **Post date:** [March 22, 2018, 1:11pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/14 "2018-03-22T13:11:06Z")
> [@Jasmine](#): > > Let’s take a look at Katrina, which was a very localized event involving one city, New Orleans. Social order pretty much collapsed. There were literally bands of roving people with guns and virtually no real help for days. This is a very commonly believed myth. > [@The Los Angeles Times](#): > > The New Orleans Times-Picayune on Monday described inflated body counts, unverified “rapes,” and unconfirmed sniper attacks as among examples of “scores of myths about the dome and Convention Center treated as fact by evacuees, the media and even some of New Orleans’ top officials.” > > Indeed, Mayor C. Ray Nagin told a national television audience on “Oprah” three weeks ago of people “in that frickin’ Superdome for five days watching dead bodies, watching hooligans killing people, raping people.” > > Journalists and officials who have reviewed the Katrina disaster blamed the inaccurate reporting in large measure on the breakdown of telephone service, which prevented dissemination of accurate reports to those most in need of the information. Race may have also played a factor. > **[Katrina Takes a Toll on Truth, News Accuracy](https://www.latimes.com/archives/la-xpm-2005-sep-27-na-rumors27-story.html)** > > Rumors supplanted accurate information and media magnified the problem. Rapes, violence and estimates of the dead were wrong. > [@The Guardian](#): > > Hyped stories were difficult to verify because of circumstance. Since the flooding confined the media largely to one area downtown, journalists could not report with depth what was happening in the neighborhoods, which created an information vacuum. Gunshots fired in the air, for example, intended to attract attention from rescuers were often translated as attacks on helicopters. > **[Misleading reports of lawlessness after Katrina worsened crisis, officials say](https://www.theguardian.com/us-news/2015/aug/16/hurricane-katrina-new-orleans-looting-violence-misleading-reports)** > > National guard coordinator and ex-governor say tales of violence and looting – which hampered rescue work and led to quasi-militia groups – were exaggerated > [@The New York Times](#): > > The narrative of those early, chaotic days — built largely on rumors and half-baked anecdotes — quickly hardened into a kind of ugly consensus: poor blacks and looters were murdering innocents and terrorizing whoever crossed their path in the dark, unprotected city. > > “As you look back on it, at the time it was being reported, it looked like the city was under siege,” said Russel L. Honoré, the retired Army lieutenant general who led military relief efforts after the storm. > > Today, a clearer picture is emerging, and it is an equally ugly one, including white vigilante violence, police killings, official cover-ups and a suffering population far more brutalized than many were willing to believe. Several police officers and a white civilian accused of racially motivated violence have recently been indicted in various cases, and more incidents are coming to light as the Justice Department has started several investigations into civil rights violations after the storm. > **[Rumor to Fact in Tales of Post-Katrina Violence (Published 2010)](https://www.nytimes.com/2010/08/27/us/27racial.html)** > > Investigations into the violence reveal cases of white vigilante violence, police killings and official cover-ups. > [@Slate](#): > > There was, of course, the purported chaos at the city’s two shelters of last resort: the Superdome and the convention center. The rape and murder of a 7-year-old girl at the convention center, dozens of killings at the Superdome, bodies piled up at both. > > But by the end of September 2005, reporting by the Times-Picayune debunked many of these stories. In fact, officials only confirmed one killing at either site: Danny Brumfield, who was shot by police. > > There were also the reports of mass looting, which led to an order authorizing police to shoot looters. Though there were many confirmed reports of looting after the storm, at least some of the alleged “looting” appears, in many cases, to have been desperate people gathering food, water, and supplies. Even early news stories included reports of people carrying food. > > But the stories of citizens shooting at relief workers and police may trump those because of the consequences. Reports of officers being shot in New Orleans appear to have contributed to the decision by officials in a nearby suburb to seal off a bridge over the Mississippi River, leaving hundreds stranded on the flooded side of the river. > **[Ten Years After Katrina, Myths About Warnings, Violence, and Recovery...](https://slate.com/news-and-politics/2015/08/hurricane-katrina-10-years-later-the-myths-that-persist-debunked.html)** > > This story was produced by the Lens, a reader-supported, nonprofit newsroom serving New Orleans. Fear of riots and looting as well as racial animus played a huge role in the hyped chaos in New Orleans after Katrina, but a major fraction of the actual violence (which is itself a small fraction of the violence that was reported at the time) was paranoid ‘self-defense’ against people (mostly black people) fleeing the flooding or seeking help. The myth is very convenient for people who want to claim that society is a veneer eggshell-thin, but it is not an accurate representation of what happened after Hurricane Katrina. The murder rate in New Orleans went from 57.1 per 100,000 person-years in 2004 to 65.3 per 100,000 person-years in 2005 to 84.8 per 100,000 person-years in 2006. Citation: [Murder Rates in New Orleans, La, 2004–2006 - PMC](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1963280/) while murders and the tragedy associated with them increased, they didn’t double, or triple. That’s an unacceptably high murder rate, it’s not the total breakdown of civil order that it’s portrayed as. Using the hype of Katrina to claim that other parts of the U.S. would descend into chaos after an EMP should be taken with a grain of salt. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 22, 2018, 1:17pm UTC](https://boards.straightdope.com/t/electromagnetic-pulse-attack-question/810879/15 "2018-03-22T13:17:47Z")
> [@Der\_Trihs](#): > > A nuclear attack on the US is a suicide attack; the aggressor’s nation will very quickly no longer exist in a meaningful fashion. **Super Computer Joshua** : _ **"A strange game. The only winning move is not to play. How about a nice game of chess? "** _ - \*War Games \*- 1983