As Rod Serling discovered, this is the stuff from which good drama develops.
I like to think that prudence would dictate that one should prepare for such an event. That being the case, if you are going to go to the trouble of being prepared, you should also make the effort to properly secure your assets. In desperate times, people who are not prepared will do whatever they can think of to secure for themselves the means to survive. If you have assets that are relatively unprotected and easy to access, then you should expect to be challenged for possession, and confronted until you are overcome. My philosophy is to first not advertise that I am well stocked and prepared for a calamity. Of equal importance is that should anyone discover that I have something of value, their efforts to acquire it would not be worth it. If the risk involved in taking something is greater than doing without, then there is no motivation for confrontation. The motivation will be to seek their needs elsewhere.
This is not to say I am averse to sharing things, or otherwise without charity. The point here is that sharing ought to be up to me, and be a voluntary thing, and not subject to duress or challenge. I can choose to share with those whom I share a general interest in, such as like minded neighbors, thus synergizing our survival efforts, or I can choose to mitigate some poor wretch's misfortune, thus providing some measure of good will, but it must always be by my own choice. Anything less is unacceptable, and indicates I have not met my obligations or responsibilities to those for whom I am accountable.
Gee, that sure sounds "survivalist" to me. I guess to me forced charity really is an oxymoron. Kinda like the government spending all my tax dollars to bail out other folks who failed to adequately prepare for a predictable outcome.
To that, I offer this link to a story about Davey Crockett. See what he had to say about our present situation:
http://www.adjutant.com/other/crockett.htm