Some people associate it with conflict and war but thoughts like this should be dispelled because football has nothing to do with such problems.
This issue arises because the US is a country that legalizes firearms. So concerns about shootings are quite natural because many tourists come from countries where the use of firearms is prohibited. It's like when you make a fuss with the wrong people in America, it's not impossible that they will bring out guns for it. I don't look down on the United States but I hope everything goes well and can hold all the matches in the 2026 world cup successfully.
Talking about the legality of firearms in the US, yes it is indeed a concern in itself, because the risk is not playing games and will be directly related to death. I hope the US or FIFA itself already has other plans to anticipate fears like this.