[2020] Combat

So I want to start with I just picked this game up from the Racial Justice and Equality bundle on itch.io and I'm absolutely loving the chance to finally play the game. I've put a ton of time into already and restarted more times than I can count just learning how to play. And that being said, the one thing I can't seem to quite get right now is combat. I've made a couple island settlements now and when I let a stranger join my community eventually I get a group of pirates coming to get them. Then they proceed to sweep up my people until I select a number of them manually to fight back. Is there a better way to prevent something from this happening? I had a couple of warriors with some gear and they all but ignored the fight until I told them to go in. Then somehow both got killed and I was left with one single guy in my village. I was frustrated a bit, but I'm already planning a new play through where I don't let random people join.