For years, excitable figures have warned that any attack on Iran would start World War III. The fact that the regime in Iran has spent decades trying to develop a nuclear weapon was always a problem for these people. After all, if a terrorist regime is developing a nuclear weapon and says it is going to use that weapon, what exactly is the world to do? Sit back and let it happen?

That’s what much of the world seemed happy to do. Or rather, it hoped that someone would take the problem off the world’s hands.

And so it fell to the governments of Israel and the United States to step up. To do what the German chancellor recently called the world’s “dirty work” for the rest of the planet.

But there are reasons why World War III has not remotely kicked off.

The first is that for the past three years, the Israelis have taken out each of the Iranian revolutionary government’s terrorist armies, one by one.

They smashed Hamas in Gaza, killing all its senior leadership and thousands of its terrorists.

They destroyed the infrastructure and leadership of Iran’s terrorist army in Lebanon, Hezbollah. They did that from the land, the sky and through history-making operations like the pager attack that killed or disabled thousands of Hezbollah’s terrorists.

They did it by taking out the leadership and weapons stores of Iran´s terrorist army in Yemen, the Houthis.

And now, for the past two weeks, with America leading the way, they have taken the battle to the head of the snake.

People should be under no illusion. The success of this American-led campaign has been extraordinary.

The world’s biggest sponsor of terror has been hit in every single place where it hurts.

The operation started by killing the supreme terror leader himself — the Ayatollah Ali Khamenei. It also killed almost all the heads of the Iranian terrorist regime and its foul military and terrorist groups.

The campaign went on to hit the remaining nuclear sites, arms dumps, missile supplies and more.

The Iranian regime responded by doing one of the stupidest things imaginable. It lashed out not just at the countries that were attacking it. It decided to try to wage war on all its neighbors. It sent drones and missiles into almost every country in the region — a great way to make friends.

But these attacks were a demonstration of weakness by the Iranian regime.

Most of its missiles and drones have been shot down before they could hit their intended targets. Meaning that for no gain, this war is now pretty much the mullahs against everybody else.

This week’s ayatollah — the son of last week’s ayatollah — is trying to talk tough in the face of all this. In a statement released yesterday, he promised to “avenge” the blood of members of his regime who have been killed. And he threatened to destroy the same amount of American assets as America and her allies have managed to destroy in his country.

I doubt it.

This week’s ayatollah is — as the New York Post put it — impotent. Perhaps literally.

Why didn’t he read out his vengeful statement himself? Why was it read out for him on Iranian state television? Perhaps it is because the ayatollah is reported to be in a coma in a hospital, having had a leg amputated after one of the US-led strikes.

There are other signs that the ayatollah’s whole empire of terror is falling apart.

What remains of his army in Lebanon made the mistake of firing off “solidarity missiles.” In retaliation, the Israeli air force hit remaining Hezbollah stations in Lebanon — including in Beirut.

Now, finally, the government of Lebanon has had enough. Of Iran.

For four decades, Iran’s army has wrecked Lebanon. It has brought nothing but war and strife for the beleaguered people of that country.

And so this week, the Lebanese government led by President Joseph Aoun and Prime Minister Nawaf Salam announced that it is outlawing Hezbollah. It has banned the group’s military activity inside the country and promised to prosecute anyone in Lebanon involved in Hezbollah activity. Even groups in Lebanon that have traditionally been allied to Hezbollah have backed this action.

Members of parliament in Lebanon are even calling for this month’s secretary general of Hezbollah, Naím Qassem, to be tried for treason and for causing insurrection against the state of Lebanon.

We will see if the Lebanese government is in a position to follow through on these threats. But whatever happens, it is a reminder of the fact that President Trump’s war against the regime in Iran is working.

Aside from the military successes, it is causing a change across the region. It is uniting countries and parties against the terrorist regime in Iran. Partly because the region is fed up with the Iranian terror. And partly because of the old strong-horse, weak-horse theory: When people see a strong horse, they wish to be on its side; when they see a weak horse, they keep away.

At present, America and her allies are the strong horse in the region. Meantime, the revolutionary Islamic government in Iran is becoming a weaker horse by the day.

There are those at home who understandably worry about aspects of the war. They are worried that the Iranian closure of the Strait of Hormuz is causing a spike in oil prices.

But once this swift and tactical war is over, those oil prices will come right down again.

Some people in Washington want hostilities to cease immediately. Others want them to stop before the operation is complete.

Of course nobody wants this war to go on a day longer than necessary. But this job can’t be left half-finished.

After all, a future US president might not have the resolve to stop the mullahs and their ambitions. Some day we’ll get another Jimmy Carter or Joe Biden.

Trump rightly started this historic mission. And he’s the only person who will also be able to finish it — on America’s terms.