Three years shy of its 50th anniversary, Iran’s tyrannical, terror-sponsoring regime may finally be nearing its breaking point. Cross your fingers.

The key question now is: What will the world — particularly America — do to ensure, and hasten, its demise, and steer it back toward a respectable position in the civilized world?

For nearly half a century, Iran’s brutal theocratic leaders have survived numerous threats: fierce internal dissent, an eight-year war with Iraq, economic sanctions and a Cold War with Israel and the United States that recently turned hot.

Yet today the regime is in, perhaps, its most precarious shape in years.

Recent events in the Middle East have shattered its regional hegemony and degraded its military.

Its economy is reeling, with inflation soaring and unemployment high.

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Its currency has collapsed, with the rial hitting a record low at 1.42 million against the dollar at free-market exchange rates last week.

Oil revenues, and the taxes they generate, are down, the result of President Donald Trump’s blessed sanctions enforcement.

Food prices are up 72% over a year ago; families can’t afford basic staples.

Even water is a problem, with much of the country having suffered months-long droughts.

All this as Supreme Leader Ayatollah Ali Khamemei, 86, is ailing, and key regime decisions are reportedly being delayed.

Nonetheless, the regime continues beat its chest: President Masoud Pezeshkian last week claimed Iran was in a “full-scale war” the United States, Europe and Israel, and threatened severe reprisals if attacked.

Military sources say the Islamic Revolutionary Guard Corps is developing unconventional warheads for ballistic missiles.

Israeli Prime Minister Benjamin Netanyahu notes that Tehran is also trying to restore its ballistic-missile production capacity; other reports suggest its nuclear-weapons program remains ongoing, despite the major setback it suffered last summer.

Economic mismanagement, repression of its people and prioritization of Iran’s military program have now triggered huge waves of fresh protests and defiance once again.

Merchants, students and others have taken to the streets in droves. Some reportedly tried to break into a government building.

“We want the mullahs gone,” demanded one student. “We want democracy.”

“Death to the dictator,” others chanted.

The situation forced government officials to ease up a bit on some dissenters and even to extend small olive branches, while at the same time warning of a “decisive response” to any attempts to foment “insecurity.”

Clearly the noose it tightening, and world pressure can make the difference.

Sanctions, for starters, are proving effective; Washington — and other nations — should look to ratchet them up.

Threats of new attacks by Israel and the United States in response to Tehran’s missile and nuclear programs are also useful.

“I hear that Iran is trying to build up again, and if they are we’re going to have to knock them down,” vowed Trump. “We’ll knock the hell out of them.” Hear, hear.

Israel has been egging protesters on via social media: “Go out into the streets together. The time has come. We are with you,” reads a Mossad post in Farsi.

Dissidents could also use help with internet access, through the use of, say, Starlink (paging Elon Musk).

Cyberattacks have also worked well.

Trump and Israel did the entire world a tremendous favor by weakening the regime militarily last year and destroying much of its nuclear facilities.

But they left cancerous cells in charge in Tehran, threatening not only its own people but the world.

It’s time to help Iranians finish off the job, once and for all.