This is not even slightly true

Go find an average cop, a CO, and a TSA employee. The CO is somewhere between a violent felon and the cop (and is technically probably both). The TSA employee is closer to a DMV employee than a cop. The border/customs agents are cops and they act like it.

To become a cop in the U.S in most places , there is already a low bar for entry. All one needs is a high school diploma (or ged) , no felony conviction and about 3 months training.