Right, you should make sure your plan for personal solvency doesn't have a single point of failure. As for global charity, do you really have a plan for that? My model had been that you are simply contributing to the support of some (possibly singleton) collection of plans. With the objective of maximizing expected good. If the true goal is something different - something like minimizing the chance that you have done no good at all and hence miss out on the warm and fuzzies - then, by all means, spread your charity dollar around.