It is said that history turns on small hinges, with the poem “For Want of a Nail” the classic example.

Another example is unfolding before our eyes.

The sudden flurry of evidence and allegations about the Biden family’s money-making schemes is a direct result of the GOP winning control of the House of Representatives last year.

The margin of midterm victory was very small — just five seats — but the impact is very large because the majority comes with subpoena power.

And aggressive new Republican committee leaders are eager and willing to use that power.

After a slow start, they are producing at near-daily pace documentation of serious wrongdoing.

None of this would be happening if Democrats still had control of the House.

The breakthroughs include testimony showing how a group of retired intelligence officials influenced the outcome of the 2020 presidential election, effectively proving the existence of a corrupt Deep State.

There are also claims from an IRS whistleblower that federal law enforcement agencies are giving favored treatment to President Biden’s son in a long-running probe and that Attorney General Merrick Garland lied to Congress about the case.

The implications of these developments are enormous and while there is still much to be learned, it is possible investigators are on the cusp of revealing one of the largest scandals in the history of American politics.

The probers believe the president participated in and profited from the corrupt influence-peddling schemes while he was vice president.

The arrows all point in that direction, with Rep. James Comer of Kentucky, head of the Oversight and Reform panel, producing bank records that show millions of dollars from China being divvied up among as many as nine Biden family members.

In response, the president emerged from hiding to say only, “that’s not true,” without directly refuting the evidence collected by banks and subpoenaed by Congress.

Meanwhile, two Ohio Republicans, Rep. Jim Jordan, head of the Judiciary Committee, and Rep. Mike Turner, head of Intelligence, revealed a former deputy CIA director testified that Tony Blinken, then a Joe Biden campaign adviser and now secretary of state, helped provoke the infamous 2020 letter signed by 51 former intelligence officials.

The witness, Mike Morell, said he helped organize the letter after Blinken called him about The Post’s initial laptop stories and later sent the letter to Blinken because he wanted Biden to win.

It hit the media just three days before the final presidential debate, allowing Biden to cite the letter as proof the laptop stories were false.

Because of the assumed credibility of the 51 signers, the letter, along with blackouts by Big Tech and Big Media of The Post’s scoops, helped save Biden from likely defeat, polls showed.

Linking the letter to the Biden campaign is significant because the president himself had to know the laptop was legitimate because the information on it included photos of him and messages and meetings.

As a Post editorial put it, the laptop was the real thing and the intel “letter was the real disinformation.”

So a Deep State not only exists, it meddled in and tilted a presidential election.

Part of that sinister force involved the many FBI former agents working at Facebook, Twitter and other tech firms, where they helped government officials censor the laptop stories and others that would have damaged Biden.

And Blinken is not the only Biden aide up to his eyeballs in dirty tricks.

Jake Sullivan, the president’s national security adviser, worked for Hillary Clinton in 2016 and helped spread the Big Lie that the infamous Steele dossier was true.

The most recent GOP bombshell involves the IRS whistleblower, who approached Comer and leaders of both parties with claims the IRS and Department of Justice are giving Hunter favored treatment.

By accusing Garland of giving false testimony to Congress, the whistleblower, identified by his lawyer as a “criminal supervisory special agent” who has been overseeing the case for three years, dramatically ups the ante.

Media wake-up call

Comer, citing what he called “the Bidens’ tangled web of complex corporate and financial records,” reacted by saying: “We’ve been wondering all along where the heck the DOJ and the IRS have been. Now it appears the Biden Administration may have been working overtime to prevent the Bidens from facing any consequences.”

The developments are so significant that even the media outlets that usually run a protection racket for Democrats have been forced to start doing their jobs.

All three broadcast networks covered the whistleblower’s claims, as did CNN, The Washington Post, The New York Times and The Associated Press.

These are the same outlets that largely ignored the laptop stories in 2020, even as Tony Bobulinski, a former partner of Hunter’s, authenticated key messages on the device, including one that referred to “the big guy” getting a secret 10% cut of a deal with a Chinese energy company.

Bobulinski identified Joe Biden as the secret partner, yet most major media organizations ignored him.

That history and a set of iron-clad double standards that always favor Democrats raise doubts about how aggressive the media handmaidens will be as new disclosures emerge.

The Times, for instance, played the whistleblower story on page 19 in Friday’s paper under the murky headline of “I.R.S. Official Is Said to Claim Political Favoritism in Hunter Biden Investigation.”

By burying the story and using the phrase “Is Said to Claim” in the headline, the editors inject skepticism into a clear, credible accusation.

The Times had the letter to Congress from the whistleblower’s lawyer, Mark Lytle, that explicitly lays out the claims and the whistleblower role in the probe, so it was disingenuous to imply there is any doubt about how specific the charges are.

Consider also that Lytle said the agent went to Congress only after he had already made his complaints within the IRS and to the Department of Justice.

The implication is that he went to Congress because he didn’t believe either agency would act on his information.

For the media, the emerging storylines represent a new chance to cover Biden honestly and accurately.

After years of looking the other way and pretending there was little or nothing to see in the laptop and other evidence, they are going to find it hard to dodge the landslide of incriminating evidence likely to come.

Still, should reporters, editors or producers be confused about whether to report new developments, here is a foolproof guide: They should simply ask themselves what they would write or say if the same set of charges and facts involved another president, say one named Donald Trump.

That should instantly clear up their confusion.

Of course, such media fairness would require a completely new mindset, but America is long overdue for a miracle.