Here is a link to an interesting document on 'Force Protection'. It is published from a military perspective, but the principles and processes can be scaled down to practical application by a prepper family, MAG, neighbourhood or community.
The website has a library of documents and field Manuals that make for interesting reading.
FM - Field Manuals ADRP 3-37 - Protection 2014-01-07
document on 'Force Protection'.