The opinions expressed by columnists are their own and do not necessarily represent the views of Townhall.com.

Having lost the election fair and square, Democrats are still seething. They have apparently decided to retaliate by attacking everything done by the new Republican administration.

First, it was the election itself. The party line -- with no hard evidence (and despite statements to the contrary by WikiLeaks’ Julian Assange) -- was that the Russians "meddled" in the election by hacking the DNC. Democrats allowed this story to morph into public confusion about whether Russia had actually “hacked” votes! (There was zero evidence of that.)

"Not my president" was already a rallying cry of those who felt betrayed by the news and the polls, having been lulled into a false sense of security that deeply unpopular candidate Hillary Clinton would win in a walk. Rep. John Lewis, D-Ga., took it further, saying, “I don’t see [newly elected president Donald Trump] as a legitimate president."

Next, the Women's March participants let the world know of their opposition to all things Trump.

Over the weekend, Trump’s executive order impacting immigrants from seven Middle Eastern countries drew a fresh round of criticism (including from former President Barack Obama).

Now, President Trump has nominated 10th Circuit Court of Appeals judge Neil Gorsuch to fill deceased Justice Antonin Scalia's seat on the U.S. Supreme Court. Gorsuch is a consummately qualified and well-respected jurist. Right on cue, the next salvo in the Left's attack on this administration (now, the judicial branch) has been launched.

First, the histrionics: Nancy Pelosi called Gorsuch “a hostile appointment.” Sen. Elizabeth Warren called him “a threat to our American values.” The Alliance for Justice characterizes him as a (wait for it) ”far-right extremist.”

Second, the hypocrisy: Predictably, Trump has been slammed for not nominating a so-called "moderate" (what the left calls a Republican who betrays his or her core values). Yet we all know that Republican demands for President Hillary Clinton to nominate someone who was palatable to conservatives would have been met by peals of laughter. (If hypocrisy were a gas, the EPA would have to ban it; we’re suffocating in it right about now.)

The hypocrisy is standard fare. The attacks on the validity of Gorsuch's seat (should he win confirmation), however, are not.

Lacking the votes to block Gorsuch's nomination (unless they filibuster, which Sen. Minority Leader Chuck Schumer is threatening), the latest petulant “news” to emanate from the left is that Gorsuch is "stealing" the seat that "should have" gone to Obama's nominee, Merrick Garland. Lefties across the country, led by The New York Times, are tweeting the hashtag #StolenSeat.

This is asinine. Scholars disagree on the obligation of the Senate to hold confirmation hearings. Even if Senate Republicans had held hearings and called for an up-or-down vote on Garland’s nomination, there is no guarantee that he would have received enough votes to get the seat. Worst of all, Joe Biden and Schumer both argued for delaying GOP nominees (Bush I in 1992 and Bush II in 2007, respectively) -- and Biden specifically called for a moratorium on judicial confirmations until the next election. (Phew! Do you smell that? Must be hypocrisy again.)

It’s clear that Democrats are doubling down on the very strategy (insults, fake news, faux outrage, deceit) that lost them the White House and Congress. This is not only a losing strategy; it is also a very dangerous game.

The democratic political processes of most western nations are civilized ways of transferring power, resolving disputes, expressing views and addressing grievances. The left is deliberately and systematically undermining the legitimacy of these institutions: voting, executive power, congressional action and judicial decisions.

They do so at their peril. People deprived of ways to peacefully express their political opinions will find ways to express them that are not peaceful. Constant attacks on the legitimacy of the American political process create incentives for people to use other, less civil means, to achieve their ends. We have seen these impulses in recent protests, violence, and threats. This is a disturbing precedent that should concern Democrats more than it does.

Unfortunately, much of the left attaches little importance to precedent, because they never intend to hold themselves to the same standard that they expect of the right -- which is to say that they behave in ways they would never tolerate from the right. The left thinks they can act out with impunity, but count on the civility of the right -- including the press' ability to shame people into submission. But I submit that that ship has sailed. In fact, the public’s mistrust of the media should serve as a warning: Democrats, solidly in control of the press, opted to compromise the press' objectivity, in furtherance of political gain. Having destroyed the press' credibility, the left cannot now trot them out as arbiters of public virtue; the damage done to the institution is not so easily repaired.

In a system that depends upon a free and objective press, that is a grave loss. But undermining the credibility -- and legitimacy -- of the entire government -- is much more serious, indeed.

So, in the spirit of democratic collegiality, I will warn the left: Choose your battles -- and your tactics -- wisely. You are playing with fire -- and we are all likely to get burned.