If you are concerned about your safety while visiting Universal Studios, you should not be. There are security officers on the grounds, and security offices are located in the upper lot by Nick Stuff and in the lower lot inside the Jurassic Park Visitors Center.
After the 9/11 terrorists attacks, Universal Studios put a heightened security program in place. Today, security precautions are constantly taken for the safety of all visitors and guests. The park stays up-to-date on all security briefings that are issued by local and federal law enforcement agencies, and always takes appropriate measures to ensure everyones safety and well-being.
To date, there have been no major security issues at Universal Studios. The park has never been threatened by terrorists or nationals. In the event that the park is threatened, again, measures are in place to ensure the safety of everyone. With this in mind, enjoy yourself and all that Universal Studios Tours has to offer leave the worrying to the people who are already equipped and prepared to deal with such an emergency, should it ever arise.