Hello. Thank you for coming to JustAnswer. I am Thoreau and I am sending this answer to you only a few minutes after you asked your question.
I'm very sorry to hear about the neighbor problems. A neighbor cannot intentionally damage or destroy another neighbor's surveillance cameras, as he would be liable for the value of the damage and he can potentially be charged with a crime. I can understand why someone would want to do that, but it's not actually unlawful to videotape areas in the outdoors from someone's own property. Further, there are other risks associated with using lasers, such as injury to people or animals.
Really, it's usually not wise to retaliate against a neighbor in kind. While turnabout may be fair play, it can expose someone to liability and it can really cause things to get way out of control. The EPA might get involved in situations where an individual is doing something harmful to the environment (for instance, if manure is contaminating a water supply). However, the best way to handle such a situation is usually to have one's attorney send a letter demanding that disruptive conduct cease and, if it doesn't, to file a lawsuit for nuisance, as a court
can require an individual to clean up matters that create unreasonable smells, sounds, etc. and order reasonable compensation to disturbed neighbors. However, doing things like flying flags, unless regulated by local ordinance or (more likely) by homeowner's association guidelines, would not usually expose someone to liability.
I'm sorry that you're experiencing neighbor problems and I hope that you're able to resolve hte matter quickly and easily. Please remember that my job here is to provide accurate information about the law. Providing bad news is the hardest part of doing my job but it's a big part of doing my job well. If you feel that the law is wrong or unfair, I'd strongly encourage you to contact your legislators, as they are the only ones who can change it.