When Ronald Reagan was elected president in 1980, many in the media considered him a dangerous extremist.

Some reporters warned that Reagan courted nuclear war and would tank the economy. He certainly was not like the gentleman Republican and moderate ex-President Gerald Ford.

But by 1989, the media was fond of a new adjective: “Reaganesque.” Reagan in retirement and without power was seen as a senior statesman.

Not so for his once-centrist and better-liked vice president, George H.W. Bush, who suddenly was reinvented as a fool and a ninny in comparison.

The transformations had already started in Reagan’s last year as president. In 1987, Newsweek magazine ran a cover story about Bush, who was running to succeed Reagan. The headline blared: “Fighting the ‘Wimp Factor.’”

“Wimp” was an odd take on someone who by age 20 had flown dangerous fighter missions in World War II and had been shot down and nearly killed. Nonetheless, the cover story hyped “a perception that [Bush] isn’t strong enough or tough enough for the challenges of the Oval Office. That he is, in a single mean word, a wimp.”

Once elected president, Bush was variously trashed by the media as a warmonger, a whiny nerd and a Reagan wannabe. After he lost his reelection bid to Bill Clinton in 1992, Bush was dismissed as a failed president.

But once Clinton’s two terms were over and Bush’s son, George W. Bush, became president in 2001, the elder Bush’s reputation was miraculously rehabilitated. The out-of-power, now-good elder Bush was used in comparisons to disparage his son, the supposedly “bad” Bush in power.

George H.W. Bush was fondly remembered as levelheaded, while his son, the new president, was labeled rash and cocky. The first Bush supposedly was now a centrist, the second Bush an extremist.

During the tenure of Democratic President Barack Obama, George W. Bush in retirement was trashed for eight years. Hurricane Katrina was allegedly his fault alone. So was the 2008 economic meltdown.

Then, a strange — or rather, predictable — metamorphosis followed in 2016.

Eight years after Bush had left office — and had kept professionally quiet during the Obama years — he (like Ford, Reagan and his father) was wondrously rehabilitated by the media.

The supposedly failed Bush presidency was reinvented by journalists to contrast positively with President Trump’s purportedly disastrous ongoing tenure.

The media now praised the former president as a moderate. Bush — whom they had once dubbed a war criminal, racist and incompetent — became a bipartisan wise man in retirement on his Texas ranch. Compared with Trump, both Bushes were now said to have ruled compassionately from the center.

Critics no longer made fun of George W. Bush’s mangled words and phrases. They were seen as misdemeanors compared with President Trump’s felonious overuse of “tremendous,” “terrific” or “loser.”

If George H.W. Bush and George W. Bush were once considered by the media to have been among the “worst” presidents in history, now they were not so bad in comparison to the unprecedented awfulness of Trump.

Why does the media despise a sitting Republican president and only ex post facto reinvent him as underappreciated?

A cynic would suggest it is not because of any fair analysis of comparative presidential achievement. Instead, the skit goes like this:

Once a Republican president loses an election or retires after two terms — and is followed by a liberal Democrat — his reputation hits bottom. But once a new Republican president enters office, the prior and now-powerless Republican ex-president is airbrushed into a model of statesmanship to contrast the ogre currently in the White House.

Republican presidencies are seen on a downward spiral of always becoming worse — by always redefining formerly despised presidents as at least better than their monstrous successors.

When a conservative president has the power to enact a conservative agenda, he is a media demon compared with his now-saintly Republican predecessors. Of course, in retirement, they have no power to do anything.

Such reinvention insidiously works to keep former Republican presidents quiet.

Former Democratic presidents Jimmy Carter, Bill Clinton and Barack Obama never quite left politics behind and often editorialize and politick from retirement.

Their retired Republican counterparts, such as Ford, Reagan and the two Bushes, each assumed a quiet, nonpartisan senior statesman role. That way, they eventually saw their presidencies mysteriously reassessed as better than the supposedly disastrous Republican administration in power at the time.

The public should grow wise to the progressive media’s formula: Once-awful Republicans are always renovated to make their party successors look worse — and thus less likely to be successful.

And the more retired Republican presidents stay quiet and nonpartisan, the faster their rehabilitation will be.

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