pull down to refresh

Do Libertarians assume the security of the group from outside influences?
How can a community thrive if it is not secure from outside influence.
My problem with Libertarian ideology is that it seems to take for granted the security of human groups when the reality of history suggests that achieving true security/sovereignty for any group of humans (or individual) is nigh on impossible without significant development of collective defensive resources...and that the most powerful groups are inevitably the ones most able to project their power upon other groups.
The wealth of nations is thus highly dependent upon the proficiency and power projection capability of their governments.