Thank you for the question. I have relatives who have worked in public security and the branch of government that deal with defense, so here is some input that I've learned from them.
No, it is not unreasonable. The roles you would find in security, either in the FBI or CIA or any other defense segment of the government isn't filled with the nation's geniuses.
That being said, there are obviously different levels of experience and backgrounds that you would need in order to work at the nation's highest branch of security, and that also depends on the type of role you would like to have. Additionally, since the FBI generally pursues federal crimes, unlike traditional local law enforcement, the qualifications will be different. For instance, knowledge of a foreign language would be looked at as a differentiating skill to the FBI, since many of those who want to work for the FBI probably have a degree in criminology or criminal justice.
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