Okay kiddo, so a "show of force" is when lots of people or things come together in one place to show that they are strong and ready to protect or defend something. It's like when you and your friends all stand together on the playground to show that you are a strong team.
Sometimes a show of force can be used to scare people who might want to do something bad, like if the police show up with lots of cars and lights flashing to scare away some bad guys who might be planning to hurt someone.
A show of force can also be helpful in making people feel safe, like when soldiers stand guard at important places to show that they are watching out for everyone and keeping them safe.
Overall, a show of force is a way for a group of people or things to show their strength and power, in order to protect or defend something they care about.