The first step is community organization and ideally advanced preparations as unprepared neighbors, can quickly become your enemy when their children get hungry and you have no extra food to spare. Having a neighborhood watch program is an excellent start, providing contacts of secure minded neighbors and some level of organization & communication. With more people in cities, you have the potential for having a sizable neighborhood security watch. At the very least, have the names and phone numbers of your neighbors and be on a friendly basis with them so you can check on them, know how they are doing and where they stand.
Second, organize a daily neighborhood meeting at a neutral location like a park, community pool, etc. to keep everyone informed. Later organize a volunteer neighborhood security watch. It doesn't have to be armed, and perhaps initially only concealed carry should be utilized, depending on severity of issues faced. Block off or restrict vehicle access to your neighborhood by parking cars across the roads or limiting access to a narrow lane that requires slowly going in and out of cars parked on alternating sides of the road. Control access in and out and limit it to residents. Inspect incoming vehicles and randomly search suspicious ones. If they refused to have their car searched, don't allow them in or post a guard to watch them. In Apartments and gated communities, deactivate the automatic exit gates that open when metal is detected, as well as the entrance gates.
In most cases, this security presence is all that will be needed in a short term Event to serve as a deterrent and divert Threats to a less protected neighborhood. But as a third precaution, or in the case where the Threats are greater, select some high vantage points with views in several directions to have an armed guard watching out. In Apartments for example, it might be a 3rd floor stairway, patio or room with windows facing two different directions. A corner lot home could serve the same function. You want two things in selecting your look out post - 1) a good view and 2) cover to protect you from gun fire (not just concealment). A roof look out position might be a good choice, but exercise care to not fall off.
Having look out points that can cover all the avenues of approach is essential. For example an Apartment Complex in the shape of a square; having a look out at each of the four corners that can see both sides of the complex fence will give not only full coverage, but provide redundancy or two diagonally opposite guards can watch all 4 sides of the complex. The addition of a roving Scout team to gather intelligence about threats outside your neighborhood might also be prudent, even if communications are semi-functional.
For increased security, the use of motion detecting alarms & lights, door alarms and trip wires can provide an added level of protection. Something as simple as fishing line strung shin high across an avenue of approach and soda cans with rocks in them tied to the ends of the string. The cans will rattle when the string is tripped. Solar powered landscape lights can be helpful, especially in power outages, by providing lights and rechargeable AA batteries. Things like these around your residence could be helpful because a neighbor on the inside could eventually prove to be one of your worst threats, especially if supplies are exhausted.
Last but not least, good communication is essential. Having MURS/FRS radios or text messaging to communicate is a good idea. Share phone numbers and set up a message group to communicate updates to. Communicate with the local authorities to assure them you will be complying fully with the law while protecting your neighborhood. Do this before one of the neighbors call and complain about vigilantes or something. In the end, a good attitude and good relationships with the neighbors are what will make this effort successful.
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