Welcome to America

Alright, listen up, genius. This joke is all about how America has a rep for being super into guns. So, when the Japanese dude rolls up and sees guns everywhere, the American's like, "Welcome to America!" because, duh, guns are basically the national mascot. It's funny because it's true...and maybe a little sad, considering you didn't get it right away, which ain't surprising for a guy like you.