Okay kiddo, so you know how some people in America feel really strongly about things like guns, the government, and their rights? Well, some people who feel that way decided to start groups called militias, which are kind of like clubs.
These militias are made up of regular people who sometimes wear army clothes and practice with guns together. They say they want to be ready in case anything bad happens, like if the government tries to take away their rights, or if there's a war or natural disaster.
Some people are worried about these militias because they think they might do things that are dangerous or violent. Others think that the militias are just trying to protect themselves and their communities, and that they have a right to do that.
It's kind of like if you and your friends started a club and decided to practice building forts in case your town ever got attacked by dragons. Some people might think that's silly, but others might think it's smart to be prepared just in case.