CHICAGO — Life on the campaign trail can be intense, unforgiving and even confrontational – but one thing it is never supposed to be is physical, a fact that appears to have been forgotten by some campaigns this year as they struggle to cope with the media spotlight.

The latest offense came Wednesday when Herman Cain’s campaign had to apologize for a bizarre incident at one of its Florida events.

A CBS News reporter was body-checked into the campaign bus by a man who at first identified himself as a journalist, then suggested he was a member of the campaign, and later turned out to be a county police officer.

ABC News’ reporter Susan Archer was pushed so hard at an event in Miami that she screamed out in protest.

These confrontations events are not likely to continue for Cain. It was announced Thursday that he had asked for and would receive Secret Service protection.

“[Homeland Security] Secretary Napolitano, at the request of the Cain campaign, consulted with the Congressional Advisory Committee, which today authorized protection for Cain,” George Ogilvy of the Secret Service said in a statement.

In the heat of the campaign season – when candidates are constantly surrounded by reporters – both sides have to exercise discipline and restraint. If reporters can’t get close enough to the candidate to ask a question or shoot quality video, then they need to accept it and deal with it. But if a candidate can’t avoid reporters – even when they want to – then it is not acceptable for security to intervene in a physical fashion.

Unfortunately, that is exactly what has happened too often this year as the Republican primary has kicked into high gear. The most egregious incident occurred in July when ABC News’ investigative correspondent, Brian Ross, was shoved by Michele Bachmann’s security team at an event in South Carolina after asking if the congresswoman had missed any votes because of her migraines.

“The staff came up and pushed me away,” Ross said on ABC’s “The View” days afterward.

At the time, Bachmann was under intense media scrutiny, not only because of her migraines but also for her status as the frontrunner in the crucial first voting state of Iowa.

In the days after the South Carolina incident, Bachmann’s security team was relentless in its efforts to keep the media away from her. As she toured Iowa that week, a team of security guards hovered constantly by her side, more as a deterrent to reporters hoping to ask her questions than because of any possible physical threat. If you managed to get close enough to Bachmann to ask a question, the security guards would step in front of you, shielding you from the candidate. When the congresswoman would leave events, the security guards would form mobile rope-lines to box out reporters as she made her way to her bus.

The over-the-top Bachmann security team quickly became notorious on the campaign trail. Months later at an event in New Hampshire, Politico reporter Jonathan Martin asked Rick Perry a question as the Texas governor stepped into his car to leave, but a security guard put his arm out and blocked Martin.

“Is this the Bachmann campaign or the Perry campaign?” Martin asked, according to reports.

Security confrontations have not been limited to Perry, Bachmann and Cain. On the very same day of the Cain campaign’s Florida incidents, a CBS reporter following Ron Paul in Washington, D.C., was reprimanded by the Texas congressman for acting too aggressively.

“Oh that’s rude. You shouldn’t push her. That’s not nice,” Paul scolded the CBS reporter.

Of course, on plenty of occasions the reporters themselves are to blame. Take a lot of young, eager reporters, put them at the forefront of a frenetic news story, subject them to the pressures of the modern media environment, and you have a recipe for disaster.

But the campaigns bear responsibility, too. Two factors stand out in particular: organization and accessibility.

In the case of the former, campaigns routinely want to opt for smaller venues to make sure they will fill up with supporters, avoiding those dreaded moments when it appears that a candidate is speaking to an empty, lackluster crowd. But by picking smaller venues – and sometimes doing so only a day or two before the event – campaigns are asking for trouble.

While, of course, campaigns want to seek the biggest possible turnout from supporters, casual onlookers and members of the media, any event that is over capacity can cause real problems for everyone involved – even Cain, himself, was the victim of some jostling at one of his Florida stops.

Accessibility is also crucial. When campaigns shut out traveling reporters from any access to the candidate by not holding media availabilities, for instance – especially at times of peak interest – reporters then try to ask questions before or after events, such as in the case of Bachmann’s migraine controversy. That sets the stage for run-ins such as Bachmann’s confrontation with Ross and Cain’s incident in Florida.

Ultimately, all sides share in the blame, but as the campaign season heats up this winter, here’s hoping that cooler heads will prevail in the end.

Matthew Jaffe is covering the 2012 campaign for ABC News and Univision.