Schneier on Security

Clive Robinson • June 21, 2017 2:04 AM

The knife looks "factory fresh" as though just out of the packet, with no hand or other marks on it.

Unfortunatly the resolution pf the download does not make the makers name visable.

Which is important because not all knives that are coloured like that are real ceramic knives. There are some realy cheap knives out there that are colourd but have ordinary quite soft metal blades.

The point needs to be made that even very soft metals like copper can be used to kill people. In fact some daggers used in cerimonial / ritulistic killing were made from them.

Man has also used the likes of dried "elephant grass" to make pointed weapons along with bamboos and similar. You can with a modicum of skill use fire to "harden" the points. Likewise certain dense woods can be made into quite effective pointed weapons.

But in a way man has been making knives as sharp as those made from ceramic for millennia using various stones including flint, jade and obsidian. The latter is also known as "volcanic glass" and has been tried out experimentaly for scalpels due to it's ultrafine edge (the sharper the knife the finer the scar). There are also quite a few crystals that can produce fine cutting edges.

The thing is most such blades are impractical for many reasons. Not least because they are too hard and brittle thus are difficult to work / machine and shatter fairly easily.

Clive Robinson • June 22, 2017 8:12 AM

@ WhiskersinMenlo,

Was there a check point cleared because the knife was ceramic, if not what was the point of reporting this detail.

Ignoring for the minute it appears not to be a ceramic knife --because we still don't know either way for certain-- and work on the assumption that the attacker thought it was.

An attacker would buy a "metal detector non trigering" knife only if they thought there was a risk of being detected prior to reaching their target. That is they would be worried of random check points with "wand down" or "portable arch" metal detectors. An attacker would not by such a knife if there were static check points, they would simply work out a way to get around them or pick another target where there were not effective static check points.

Thus this would suggest that random "wand downs" by the security services would cause attackers more problems than static checkpoints.

Without going through the math it would appear that if security resources are limited you would take static security measures at high value points and random measures in most other places.

However a word of caution, to save resources some might feel that aggregating high value targets into a small area would make most value of static resources. Actually it probably would not, because it would make such a target of considerably increased value thus the attacker would have more incentive to attack it in ways they would not otherwise have considered. That is rather than a simple use of vehicles, knives and guns they would look at smuggling in explosives or the components of explosives or developing new weapons such as rockets, glider bombs and drones. This requires educated attackers, and usually such people do not regard themselves as "disposable DNA". The result is that they will also learn by their mistakes, where as the "I give my life" types won't and thus not become more effective with time, unlike the defenders.

Put crudely you do not want to "educate your attacker" because this makes them a rather more formidable opponent. Even in asymmetric warfare brains are still the number one asset for either side. There is an old military saying "Don't leave ammunition for the enemy" forcing them to become more thoughtful and learn from their mistakes is probably a lot worse.

At the end of the day you also need to understand the attackers motives. Often they are actually not looking to do significant direct damage but cause much larger damage by indirect means. That is they want to create fear uncertainty and doubt. Thus when played correctly the fear becomes a paralyzing agent and thus much more significant damage results.

This is the same as the "Long Gun Effect", a sniper does very little damage, much less than a couple of mortar rounds. But the fear of a sniper is "in their area" can demoralize entire battalions and make them unfit to fight effectively (which is a reason why few snipers ever make it as far as being a POW).

The reason it's so effective is because it feels "personal not random", your imagination can almost feel the gaze through the scope and imagine how you are being evaluated by some unknown criteria to be singled out for death or not, never knowing if you have been "passed over or not".

To a lesser extent the same sort of thinking stops people wanting to travel to, or trade with a place, where there are such fears.

Trying to reduce such stress can be an almost immeasurably large burden when it comes to resources. Because not only does the deterrent have to be seen, it has to be seen to work, not just by a reduction in the number of attacks, but by actually catching attackers before they do so. It's a big ask, which is why quite a few suspect that authorities are "making patsy attackers" so that the authorities "can be seen to be effective"...

Even when an attacker has not reasoned this out they can see by the way society changes that any attack will be newsworthy, the questoon is thus in what way. That is they will also see that non targeted or random attacks do not work as well in their favour.

This is in part because people start to realise there is little that can be done against random attacks, and a more fatalistic attitude starts to predominate in the way it does with accidents, or as is seen in war with the dropping of bombs. But there is also the issie of "killing of innocents", it does not "work for the cause" in fact the opposite. Thus attackers have to go for identifiable targets in the publics mind, those in effect payed from the public purse to defend the public in a hostile or premptive manner.

That is random does not work as well for attackers as it does for defenders. Leaving the question of if attackers have realised this and thus if an advantage can be made of this difference by the defenders...

And I suspect it can with "random checking" more presence / boots on the ground and perhaps supprisingly a decrease in weapons in view. The latter point being that having a gun in effect legitimizes you as a target not just in the attackers minds but also in the publics mind as well, it's the reason a wise politician "keeps troops off the streets" or police that look like troops of the streets.

Clive Robinson • June 23, 2017 11:18 AM

@ JG4,

When looking at the NY Times and stories about Mexico, it helps to remember that a certain mexican has an increasing amount of financial leverage on them,

http://abcnews.go.com/Business/story?id=6690579

As well as other US organisations that deal with "the media" citizens get their news, entertainment etc by...