I find the idea that today we still have to worry about an en masse invasion from a random blob of the same planet and specie population quite an aberration...

I find the idea that today we still have to worry about an en masse invasion from a random blob of the same planet and specie population quite an aberration... And more disturbing it all starts usually from single individuals....you want to start a war? Good luck! Good for you! should be the answer of the rest of the population, why it doesn't happen? Lack of education, and the perception of unlawfulness? Armed enforcement? It's beyond me...