What may seem like acts of random violence – from nation-shaking terror attacks to mass shootings to run-of-the-mill street muggings – are "as predictable as boiling water," a protection specialist told Fox News Digital.

"You have to know what you're looking for," said Sam Rosenberg, a retired U.S. Marine who's protected celebrities like Tom Cruise and world leaders like Israeli Prime Minister Benjamin Netanyahu.

Most violent crimes have an element of predictability that follows a four-step model that he calls "T.I.M.E.," which stands for target selection, interview/intelligence, method of attack and escape. 

"The basis of my book is that I don't believe that violence is random," Rosenberg said. "Most people have this tendency to use that term when they call violence random. The news uses it all the time. But it enables this mentality that says, 'Well, if violence is random, there's nothing anyone can do about it, because it is unpredictable.'"

SHOOTINGS AROUND COLLEGE CAMPUSES LEAVE STUDENTS, FAMILIES ON EDGE: ‘EVERYONE IS AT RISK’

Rosenberg used common street-level crimes that the average citizen would likely face, such as a robbery, to explain the "T.I.M.E." method. 

He did the same using sexual assaults as an example, which is a crime many college-aged students contend with.

The "bad guy" picks a target through screening, or "interview," which can be an aggressive approach, like someone chasing a victim through a dark, empty subway, or a subtle approach through persuasion, which is more common in sexual assaults, he said. 

BODYCAM CAPTURES DRAMATIC SHOOT-OUT WITH MAN ACCUSED OF SLAUGHTERING FAMILY BEFORE VANISHING

"Typically, the victims are ‘soft targets,’ meaning they're vulnerable. In sexual assaults, the victim is naive, too drunk or younger," Rosenberg said. "That's all part of the intelligence stage. Bad guys want a soft target, a target that is easy, who cannot or will not fight back.

"You may be walking down the street and not even know that there's a predator out there looking at potential targets for something like rape, robbery, murder or whatever it is.

"You may be at a party or at a concert, and if that bad guy sees you as a potential target, they certainly have a method of attack in mind. They probably have an escape plan or some kind of plan to follow."

FBI SQUAD TARGETING SINISTER ART UNDERWORLD SAVES MONET, YANKEES MEMORABILIA

But what they likely don't have is the vetting.

"Are you going to pose resistance? Is this going to be a challenge? If yes, they'll likely move on," said Rosenberg, who wrote a book called "Live Ready," available in December, which is predicated on keying into these clues.

Then it becomes a method of attack – aggression or persuasion, in most cases – and how they'll get away with their crime, he said. 

That ranges from a physical escape out of a subway station to date-rape drugs to suicide or suicide by cop, he said. 

The same method, he argues, can be applied to large-scale attacks, such as a mass shooting or a 9/11-style terror attack.

TEXTS, LETTERS FROM MAINE MASSACRE SUSPECT'S ARMY COLLEAGUES WARNED HE THREATENED ‘SHOOTING UP PLACES’

The difference between street-level crime vs. a sexual predator who's grooming his/her victim or a terrorist organization plotting an attack to shake a nation is how long the "interview process takes," Rosenberg says.

"You know, 9/11 took five years for the ‘I’ in ‘T.I.M.E.' to be completed. In the case of a straight, street-level attack, it might just be a few moments," Rosenberg said. 

Sexual-based crimes, he said, are typically in the middle and can take "weeks or months, where that persuading predator is trying to break down someone's resistance and create those opportunities for victimization." 

During that interview phase, Rosenberg said the criminal or predator gauges the victim's reaction to certain things. 

"Do you allow them into your personal space? Do you allow them to sort of take certain liberties or violate certain social boundaries? Do you override your natural inclination to try and avoid someone because you don't want to be rude?" Rosenberg said. 

A potential predator "assesses" all these behaviors and actions. "Sometimes they just take the form of following you and seeing if you're even aware of their existence," he said. 

"I have seen a massive upsurge in not only the level of violence, but violent crime in general," Rosenberg said. "I truly believe that our population right now is incredibly desensitized to violence. 

"There are many more people willing to commit violence. I think that we have a very, very deeply disturbed segment of our population that are more likely to commit mass homicides, if they get to the sort of level of psychology where that becomes viable, if you will, in their mind."

That's evidenced by Gun Violence Archive's recent graphic showing that the United States could surpass 700 mass shootings this year, which is typically defined as four or more casualties. 

"I also believe that we have seen an upsurge in what is called spectator syndrome," Rosenberg said. "So you know, everybody has this good advice, things like, you know, walking groups, traveling groups, things like that. And that's logical. I'm not saying that's a bad idea. 

"But a lot of people, what they do is they assume that if I'm around other people, other people will protect me. And what we've seen in the last 10 to 15 years is this change where people will whip out their camera phones and film (instead of calling 911 or getting involved)."

BYSTANDER TOOK BULLET RECORDING FINANCIER KILLING FAMILY MAN IN ROAD RAGE MURDER: POLICE

Part of that, he said, is fear for their own safety, or they want to film it for social media. 

Just a month ago, in late October, Samuel Gomez saw one man bleeding on the ground and another in a car with a gun in hand as he walked out of a downtown Portland, Oregon, hotel. 

He filmed the gunman, and he took a bullet in the leg and narrowly missed a second bullet. 

Rosenberg wrote a book after 25 years of protecting people "because this information is simply not out there."

CLICK HERE TO GET THE FOX NEWS APP

"The average person simply doesn't know they're not helpless. They don't know what factors they can control," Rosenberg said. 

"My personal conviction is that violence is never random and you are never helpless. You just have to understand two factors, how to make sure that you can think and make the right decisions under stress and understand the situational factors that we can all control."