Michael Moynihan Cautions Celebrating CEO Murder Is Disastrous Slippery Slope

Admiration for the man suspected of murdering the UnitedHealthcare CEO is not just perverse ... it's dangerous, Michael Moynihan tells TMZ.

The renowned journalist told "TMZ Live" ... the level of joy and satisfaction a portion of the country felt when Brian Thompson was killed last week is deeply disturbing ... but not nearly as grotesque as people fawning over Luigi Mangione.

MM contends our society is clearly in a "sick place" ... and most of the people who see Mangione as a folk hero are too young -- and uninformed -- to really consider the twisted logic of the heinous crime.

Michael tells TMZ it is a very slippery slope if the murder of Thompson is allowed to be seen as a forgivable or even justified act in the public eye ... which could lead to other CEOs being murdered in the name of righteous views.

Perhaps the most disturbing aspect of the Mangione support ... his admirers are not fringe! It seems -- to Michael -- there are more people who care about the suspect than care about the murder victim or his family.

As TMZ previously reported, Luigi was first named as a person of interest earlier this week after Thompson was gunned down in front of a midtown Manhattan hotel on Dec. 4.

Luigi was picked up in an Altoona, PA McDonald's after a customer spotted Luigi and recognized him from widely shared suspect pics ... prompting an employee to call police.

From there, Luigi was arrested on firearms and forgery charges in Pennsylvania before being hit with a second-degree murder charge by the Manhattan D.A. He's currently fighting extradition to NYC ... with his attorney previously sharing Luigi plans to plead not guilty.