You see few authentic political shockers anymore, and when Supreme Court Justice John Roberts sided with the court’s liberals to uphold President Obama’s health care reform law, that was one of them.

But, merits of the law aside, an underlying truth about the resulting shock is that there is utter disbelief in 21st century America that a partisan can truly change his mind and not do so out of Machiavellian calculation or an inability to resist “caving” to opposition political pressure.

A second underlying truth that those who regard the center as mushy, wishy washy people who can’t make up their minds — rather than people who may often wait a little longer to reach an informed conclusion — won’t like to hear is this: for whatever reasons it came down as it did, the final ruling meant the country’s fragile center prevailed.

A centrist and moderate may not be a declared centrist or moderate or even a centrist and moderate consistently. In his superb book “Leading from the Center: Why Moderates Make the Best Presidents,” historian Gil Troy classifies Ronald Reagan as a moderate due to Reagan’s willingness to work with and compromise with the opposition, rather than dig in his heels and take all-or-nothing positions.

In today’s ever dogmatic Republican Party, Roberts’ action provoked howls that were akin to Julius Caesar’s “Et tu, Brute?”

Conservative news outlets such as the Wall Street Journal blasted Roberts (“swayed from (his) constitutional duties…”). Web powerhouse talker Glenn Beck labeled George W. Bush a “progressive” for picking Roberts and took pre-orders for a t-shirt with Roberts’ picture on it with the word “Coward.” Conservative politicians, talk-show hosts and bloggers dumped on Roberts so much that a new John Roberts Landfill may open soon.

Meanwhile, CBS’s Jan Crawford did a report based on info from “two sources with specific knowledge of the deliberations” detailing how Roberts changed his original position to vote with the liberals. Were her sources conservative justices’ law clerks out to expose what they considered Roberts political heresy? If so, this unprecedented leak of Supreme Court deliberations would be yet another reflection of how in America’s ideological wars, partisans try to discredit those who deviate from an ideological line.

Mind-changing no longer allowed? Writes The Moderate Voice’s columnist Shaun Mullen: “I have come, however circuitously, to the view that the ability to change one’s mind about things that matter is a mark of maturity — and sometimes greatness.”

The Daily Beast’s Michael Tomasky, citing parts of the CBS report about how conservative justices angrily refused to join Roberts in any of his positions at all once he switched from theirs, notes that conservative GOPers are playing a politically nonproductive zero sum game: “From the base to Congress to the members of the Supreme Court, it’s the same mentality. Everything or nothing. Well folks, on health care, and on the stimulus, and on financial regulatory reform, and a handful of other things, you got nothing. When might you bother to stop and think about whether this strategy is paying off? You won’t, because it’s not a strategy. It’s a primal instinct, driven by rage.”

Rage rather than serious policy debate fuels early 21st century politics, much of it stemming from both parties’ bases. Liberal Democrats go hunting for DINOs (Democratic in Name Only), while conservative Republicans go hunting for RINOs (Republicans in Name Only).

They’ve got political heads to mount on their ideological walls, but in the process many Americans now consider them both PSINOs (Problem Solvers In Name Only).

Roberts is now attacked by the right, which has the attitude: “Oh, if only we had more great, objective, patriotic judges like Antonin Scalia and Clarence Thomas!” He’s now attacked by the left, which fears his ruling was a mere charade or judge’s version of a magician’s misdirection. Neither side really trusts Roberts.

Hey, wait. This is deja vu for moderates, centrists and independents. Now I know what it is:

Mr. Roberts: welcome to being — for now, at least — a member of America’s political center.

Copyright 2012 Joe Gandelman, distributed exclusively by Cagle Cartoons newspaper syndicate.