You CAN purify your own water. You CAN store a few weeks of food in your closet. You CAN keep your gas tank at least 1/2 full. (I know more than one person who had to wait in line on 9/11 because they were out of gas. And things were back to normal the next day in that case!)
In the longer run, it may be a good idea to put a slightly larger portion of your money into more stable investments. Precious metals have been rising for the past several months. Land tends to be good too. Of course the best hard-times advice I ever heard was to get out of debt.
I'm not saying that anything IS going to happen but it certainly seems like conditions are ripe.