It begs the question, would Rand have been willing to die in defense of her beliefs? Would she have expected others to do so? If a Randian utopia, a Galt's Gulch were established and came under attack, would its citizens band together to repel the threat and face mortal peril for the good of their fellow man (and in doing so violate their own canon), or would they merely stand fast and just defend their own property?
They banded together to create it and maintain it. Why would you expect they wouldn't band together to defend it?