Consider multi-levels walls of protection

After reading about how IT people will create more than one wall of protection to increase data security from cyber attack. They should do the same around buildings (schools, churches, malls, airports) as well. There could be one (figurative) wall completely at the outside of these buildings (i.e. parking lots.) They would build mini indoor "checkpoints" staffed with service dogs. These checkpoints would be "layer 1" of this wall of protection. In addition to this, they could place checkpoints right at the entranceway of certain buildings mentioned above (i.e. airports) as well. This could be "layer 2" of this wall of protection. These multi-level walls of protection are more secure than that of just one wall. However, people would be hesitant to live in such a "police state" by having these multi-levels of walls of protection to go through just to shop or fly. To remedy this, can they create so called invisible high tech checkpoints to where people will not even noticed they just passed a wall of protection? Just like they do with computer data from cyber attacks, I believe they ought to build multi-layered walls of protection to increase security around buildings mentioned above.