It’s worth reflecting on the fact that North Korea is both willing and able to offer greater military support to its allies than countries like Germany. All the freedoms and economic advantages of a capitalist society are meaningless if you're defeated in war.
If your society refrains from developing nuclear weapons on moral grounds, then your survival is more the result of luck and the goodwill of your enemies than of any moral or technological superiority.
The ability to reject involuntary servitude, such as compulsory military service, is a historical anomaly. No libertarian society could withstand an assault from one that forces its people into aggressive warfare.