Okay kiddo, let's talk about British nationalism. It's like when you feel really proud of where you come from and you love your country a lot. British nationalism is when someone feels that way about Great Britain.
You know how you might say "I love my family" or "I love my friends"? Well, people who are into British nationalism might say "I love my country" or "I love being British".
Some people who are into British nationalism might think that their country is the best in the world and that it should always come first. They might want to make sure that their country stays strong and is always successful.
But sometimes people can get too caught up in their love for their country and forget that other countries matter too. It's important to remember to be respectful to everyone, no matter where they come from.
So that's a basic idea of what British nationalism is. It's like being really proud of Great Britain and feeling like it's the most important place in the world. But we also need to remember that everyone is important, no matter where they're from.