There is more truth to what you are saying than many Americans want to believe. In 2006, the FBI issued a nationwide alert to police departments that some while supremacist and white nationalist organizations were making a concerted effort to recruit both military and law enforcement personnel.
Three years later, the Oath Keepers, one of the better known militias, was formed. They only admit active duty or veteran police officers and members of the military to regular membership (other people aligned with their beliefs can become associate members). Currently, information leaked from the Oath Keepers suggests a membership of about 38,000. Civil rights organizations and police units that monitor domestic terrorist organizations dispute that, saying the active membership is about 5,000. Twenty of those indicted after the January 6th attack on the U.S. Capitol were members of the Oath Keepers--far more of their members likely participated.
The affinity between rightwing extremists and police officers is fairly obvious: the culture of the uniformed services (police and military) tends to be conservative, so they are thought to be more susceptible to the extreme rightwing views of these groups. And, perhaps more chilling, military and police personnel know how to use weapons and are trained to take orders.
Unfortunately, these extremist groups have proliferated during the Trump presidency. In 2017, approximately 100 white nationalist/supremacist groups--some counting only a dozen or so members, while others command the loyalty of thousands--were active for at least part of the year. By 2020, that number had risen to more than 150.
Thanks for sharing your thoughts, Walter.