I often hear that argument and it's interesting but then how to do you square it with Us history? Slavery and legal apartheid were legal for a long time, how co

I often hear that argument and it's interesting but then how to do you square it with Us history? Slavery and legal apartheid were legal for a long time, how come guns didn't stop that tyranny? During WW2, thousands of an ethnic minority (Japanese) were moved into camps against their will will the war was on. How come guns didn't stop that tyranny? I question whether a well armed people are capable of stopping a tyrannical government...