#why can an entire army be beaten by a group of Englishmen

[galaload]

So I have been playing fallout 3 recently when I found an old disc of it that was backwards compatible with the Xbox 1. I have a question, why is the combat knife with the tunnel snakes jacket op? Because I helped the brother hood of steel kill a large number of super mutants with a combat knife, and when the enclave invaded I think the Washington monument I killed two of their soldier who were wearing power armor with a combat knife. It makes no sense that a knife wielding vault dweller wearing a leather jacket could stab through power armor to kill military trained soldier. If this is possible then what’s stopping a large group of raiders destroying the enclave with nothing but combat knives?

TLDR enclave can be stabbed to death easily and that doesn’t make sense

I love this game