Report what you hear to the FBI and local cops, then they can take the surveillance footage nearby and hopefully have you identify them on camera. Otherwise I don't know. It's extremely idiotic to say Americans "can't do anything" though, "everyone is fat in America" is simply just a meme used to slander us. The sad truth is even if there were some terror attack most Americans probably wouldn't care very much. Most would see it on the news and shrug and in about a day later everyone would go back to whatever it is they were doing. Furthermore it won't do anything to stop our government from bombing Iran or Gaza, they keep on doing whatever they want whether citizens like it or not.