This is how communication on the internet works.
Person 1: I like vanilla ice.
Person 2: Why didn't you say chocolate?
Person 1: Well it's good but I just perfe...
Person 2: YOUR A NAZI!
Person 1: What?! I was talking about ice cre...
Person 2: <invites person 3, 4 and 5>
Person 2, 3, 4, 5: NAZI, WE HATE YOU SCUM!
The real reason why mustard gas is seen as a big no no now is because big ketchup was mad that they couldn't have a gas, so they did everything they could do get mustard gas taken down and it succeeded. This is definitely factual history and you should 100% believe everything you read on the internet.