The defense in depth thesis is that you are best off investing some resources from your limited military budget in many different defenses (e.g. nuclear deterrence; intelligence gathering and early warning systems; an air force, navy and army; command and communication bunkers; diplomacy and allies) rather than specialising heavily in just one.
I’m not familiar with how this concept is used in the military, but in safety engineering I’ve never heard of it as a tradeoff between ‘many layers, many holes’ vs ‘one layer, few holes’. The swiss cheese model is often meant to illustrate the fact that your barriers are often not 100% effective, so even if you think you have a great barrier, you should have more than one of it. From this perspective, the concept of having multiple barriers is straightforwardly good and doesn’t imply justifying the use of weaker barriers.
Right, but because we have limited resources, we need to choose whether to invest more in just a few stronger layers, or less each in more different layers. Of course in an ideal world we have heaps of really strong layers, but that may be cost-prohibitive.
I’m not familiar with how this concept is used in the military, but in safety engineering I’ve never heard of it as a tradeoff between ‘many layers, many holes’ vs ‘one layer, few holes’. The swiss cheese model is often meant to illustrate the fact that your barriers are often not 100% effective, so even if you think you have a great barrier, you should have more than one of it. From this perspective, the concept of having multiple barriers is straightforwardly good and doesn’t imply justifying the use of weaker barriers.
Right, but because we have limited resources, we need to choose whether to invest more in just a few stronger layers, or less each in more different layers. Of course in an ideal world we have heaps of really strong layers, but that may be cost-prohibitive.