In this hypothetical scenario of a generic Moslem visiting a public festival I thought the words “might be their intention to come with swords” didn’t preclude the fact that many Moslems want to kill non-Moslems.
So, it isn’t difficult for me to understand.
Here is the phrase I was responding to, not a reference to a public festival, football game or pet store.
"Came to a Christian festival" is a wholly different concept.