A play in Central Park delights the audience with the brutal assassination of the president.  A comedian amuses her followers by holding a replica of the severed head of the president.  To adoring fans, a pop singer revels in her dreams of torching the White House.

When sick fantasy evolves into reality, a lunatic shoots a congressman in a public park, and a prominent journalist suggests we consider that the victim brought it on himself.

At colleges and universities, a gaggle of leftist students decide who can and cannot speak by fomenting violence against speakers they do not want to hear.  Milquetoast college administrators take the path of least resistance and direct the police to stand down.  One University of California, Berkeley administrator, denying that anyone was told to "stand down," defensively insisted police were instead told to "hold your post," creating a distinction between the two without a difference.

These administrators are inflaming the passions of thugs.  The fires next time will burn brighter.  The shards of glass will be more numerous.

Those lusting after the president's assassination fail to comprehend that it is not Donald J. Trump they are attacking; it is the political system.

Nearly two hundred years ago, Alexis de Tocqueville, a French civil servant, or in the parlance of leftist identity politics, a "Dwem" (dead white European male), wrote a classic two-volume tome, Democracy in America.

For Tocqueville, compromise and conciliation are the very essence of democracy.  That means an ability to divorce unbending ideology in order to embrace the pragmatism that produces results.  It means viewing the opposition not as some group of demons, but as compatriots who seek the common good by different means.

The foundation of any political system is its legitimacy.  The ineffectual Russian tsars continued for centuries as long as the masses believed that the tsar was anointed by God.  The French aristocracy ruled for 400 years while failing to meet their political obligations.  They were vanquished in the flicker of a historical sunset when their legitimacy was no longer accepted.

As for those who cheer for the assassination of the president, find justification in the shooting of a congressman, and believe they are the gatekeepers of basic rights, it is not the administration they are attacking, but the values of our democracy.  They are creating an impermeable divide where no compromise will be possible.  They are inflicting wounds on the body politic that will not heal.

When neither side recognizes the legitimacy of the other, when we are all stained as deplorables by one another, the very foundations of the system are prone to collapse.

Loyal opposition is enshrined in our democratic heritage.  But when opposition to an administration justifies the use of violence, it is not the administration that is under attack, but the very civility without which a democracy cannot function.

Abraham H. Miller is an emeritus professor of political science, University of Cincinnati and a distinguished fellow with the Hyam Salomon Center.