While I have no definitive proof of this, it would seem to me that there has actually been advancement in the area automobiles that have increased their lethality. Mainly more powerful and efficient engines, and other such refinements in design which make them more robust, easier to use, and handle better increasing their utility as a weapon. I realize this is a bit vague, I am not an engineer, but it would seem to me that if I had to choose between a truck produced in the first half of the 20th century or a modern model, the former would likely not be my first choice for a vehicular assault. Of course this is not say that the changes are prohibitive for their use just that it seems to me that there probably has been some relevant changes.
Secondly, I am not sure the actual problem is simply the idea. Take the case of tampering with medication. You point out that regulations were put in place afterwards that made it harder to tamper with medication. However this makes it seem that the subsequent lack of tampering cases may be linked to this, when it is more likely that the first case was simply an outlier. In the past, especially in america, there has been a long history of completely unregulated drug markets, and dubious cures sold out of the back of carts. Many products such as soda often started out as questionable curealls. For instance coca cola was made with actual coca (the plant cocaine alkaloids are derived from) and sold as a cure for headaches. Other drug-laced, or even mildly toxic products were often sold to the public in great quantities. As such there have been many times that anyone with the will to tamper with medications and trick people into consuming poisons has always been possible. In fact it has been quite easy. This holds true not just for medications, but for many consumables that change hands several times on the way to the consumer.
I think the limiting factor here is not the idea, nor the accessibility of means to inflict harm, but instead the lack of will to kill indiscriminately on the part of most humans. Even during wars I have read it is common for most soldiers to deliberately miss the enemy (Dave Grossman's On Killing, although I think some of the claims in that book may have been called into question by more recent research). I would guess it is the case that most of these attacks are unified more by the fact that they were committed spur of the moment by individuals with rare combinations of mental traits and social environments. It is the rarity of such people, with whom the idea enables which is crucial. Further I would say that the idea doesn't cause these people to act violently, it instead adds to their repertoire of possible violent actions, from which they would likely choose either way.
Of course, that is not to say that meme transmission has little to do with the expressions of violence, it is of course of utmost importance in shaping most of our behavior, I simply do not really believe it is the factor of importance in this case.
Finally I just want to say that it strikes me that the idea of "dangerous information" is similar to the idea of computer security by obfuscation. The problem with "security by obfuscation" is that it often also impedes solutions to various attacks, it only works if your opponent has no way of guessing as to how to defeat your security. If I recall correctly that was the justification of releasing the genetic sequence from the research on what mutations could cause the avian flu virus to go airborne. While it is also true that this could enable someone to induce the same change into flu virus, it was judged more important for the scientific community to understand the genetics of pathology. Even if it wasn't released, it would not have taken much for any similarly equipped bio-weapons research lab to turn out the same result. Creating just as much, if not more, danger than public release. As such I tend not to agree with trying to withhold information, unless it can be reasonably established that the information is oddly asymmetric in it's cost and dangers (If some mad genius figures out how to macguyver a nuke out of chewing gum, baking soda, and bits of string, that would certainly be worth keeping secret.)
Well anyways sorry for the longwinded rambling post, just my two pence.
While I have no definitive proof of this, it would seem to me that there has actually been advancement in the area automobiles that have increased their lethality. Mainly more powerful and efficient engines, and other such refinements in design which make them more robust, easier to use, and handle better increasing their utility as a weapon. I realize this is a bit vague, I am not an engineer, but it would seem to me that if I had to choose between a truck produced in the first half of the 20th century or a modern model, the former would likely not be my first choice for a vehicular assault. Of course this is not say that the changes are prohibitive for their use just that it seems to me that there probably has been some relevant changes.
Secondly, I am not sure the actual problem is simply the idea. Take the case of tampering with medication. You point out that regulations were put in place afterwards that made it harder to tamper with medication. However this makes it seem that the subsequent lack of tampering cases may be linked to this, when it is more likely that the first case was simply an outlier. In the past, especially in america, there has been a long history of completely unregulated drug markets, and dubious cures sold out of the back of carts. Many products such as soda often started out as questionable curealls. For instance coca cola was made with actual coca (the plant cocaine alkaloids are derived from) and sold as a cure for headaches. Other drug-laced, or even mildly toxic products were often sold to the public in great quantities. As such there have been many times that anyone with the will to tamper with medications and trick people into consuming poisons has always been possible. In fact it has been quite easy. This holds true not just for medications, but for many consumables that change hands several times on the way to the consumer.
I think the limiting factor here is not the idea, nor the accessibility of means to inflict harm, but instead the lack of will to kill indiscriminately on the part of most humans. Even during wars I have read it is common for most soldiers to deliberately miss the enemy (Dave Grossman's On Killing, although I think some of the claims in that book may have been called into question by more recent research). I would guess it is the case that most of these attacks are unified more by the fact that they were committed spur of the moment by individuals with rare combinations of mental traits and social environments. It is the rarity of such people, with whom the idea enables which is crucial. Further I would say that the idea doesn't cause these people to act violently, it instead adds to their repertoire of possible violent actions, from which they would likely choose either way.
Of course, that is not to say that meme transmission has little to do with the expressions of violence, it is of course of utmost importance in shaping most of our behavior, I simply do not really believe it is the factor of importance in this case.
Finally I just want to say that it strikes me that the idea of "dangerous information" is similar to the idea of computer security by obfuscation. The problem with "security by obfuscation" is that it often also impedes solutions to various attacks, it only works if your opponent has no way of guessing as to how to defeat your security. If I recall correctly that was the justification of releasing the genetic sequence from the research on what mutations could cause the avian flu virus to go airborne. While it is also true that this could enable someone to induce the same change into flu virus, it was judged more important for the scientific community to understand the genetics of pathology. Even if it wasn't released, it would not have taken much for any similarly equipped bio-weapons research lab to turn out the same result. Creating just as much, if not more, danger than public release. As such I tend not to agree with trying to withhold information, unless it can be reasonably established that the information is oddly asymmetric in it's cost and dangers (If some mad genius figures out how to macguyver a nuke out of chewing gum, baking soda, and bits of string, that would certainly be worth keeping secret.)
Well anyways sorry for the longwinded rambling post, just my two pence.