Back in '90 in San Diego a burglar ring was busted. Their MO was to canvas the neighborhood going door-tpo-door asking people to update their canine registry..."Do you folks still have a dog? Just need to update our registry."...that sort of thing. The cops found a map with all the dogs in the neighborhood highlighted. Throu military housing and civilian housing...didn't matter. The houses with dogs weren't hit. Burglars look for the path of least resistence. It's a shoppers market for them, and unless they know you have exactly what they want they're more liable to pick the soft targets.
The home invasion scenario is more problematic. A dog can/may delay an intruder long enough for you to get to the gun. My plan if it came to that would be to come out shooting, castle law bedamned. Let 'em prove I wasn't scared for my life. (If I have time I'll put on a dress and a wig and grab a butcher knife and start yelling, "Oh. mother! What have you done!? Oh, the blood...all the blood", then run out and greet them when the dog's done.
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