He came. He saw. He laid waste to his enemies.
The boomerang thrown by president George W Bush in his 2002 State of the Union address against the "Axis of Evil" where he identified of rogue states hell-bent on weapons of mass destruction — Iraq, North Korea and Iran — has come back 15 years later into the hands of his Republican successor, Donald Trump.
We know what happened to Iraq, which did not have a nuclear program.
Mr Trump's cause and targets are similar. North Korea is a renegade nuclear state outside the rule of international law. Iran is an incipient nuclear state, but today under the bounds of a substantial international contract that prevents its development of nuclear weapons.
But to Mr Trump the difference does not matter. North Korea is threatened with destruction. The nuclear shackles on Iran will be voided by Mr Trump if he can — and the threat of Iran's destruction cannot be far behind a nuclear-fuelled Iran's continued declaration of the states it wants to destroy across the Middle East — from Israel to Saudi Arabia.
Trump not asking for permission
Mr Trump has also turned away from the juridical framework of the UN.
Before initiating war with Iraq, Mr Bush made concerted efforts to secure a resolution authorising the use of force in the Security Council. It ultimately failed, and war nevertheless followed, endorsed by most of the principal nations of the developed world.
Mr Trump is not even trying to seek the permission, endorsement or consent of the Security Council.
Today, the President simply states that North Korea will, if it does not yield, be destroyed.
War with North Korea appears closer than ever before. And he has not even gone to Congress to seek a declaration of war.
With respect to Iran, if the United States exits the agreement he despises, it is not at all clear that other signatories who are US allies will follow — precipitating a major split with the countries the US worked most closely with to bring Iran under restraint.
If the US voids at least its part of the deal, Iran's reaction will determine if a nuclear breakout in that country is the next step.
Are institutions crumbling?
Over the past two days, Mr Trump has made measured statements of support for the UN and its principles and outlined sensible reforms that the world body has been long overdue in addressing — and at his side was the new Secretary-General, which was an important statement of willingness to work on such an agenda.
That is the good news of this week in New York.
But the issue posed by Mr Trump's inauguration, for America and its engagement with the world, has been from the beginning: are the institutions that constituted the post-World War II era of security and prosperity crumbling — through unilateralism, protectionism, isolationism, exhaustion? And will they continue to be led by the United States as the leader of the free world?
If they are indeed, crumbling and American leadership is indeed weakening — by policies and temperament that tend to isolate the United States and drive a wedge between America and most of the world — then we are truly entering a new, less certain, and likely more unstable and more dangerous world.
The past 70 years have hardly brought the world peace that is the founding spirit of the United Nations, and to which Mr Trump paid tribute. Nor has poverty been eradicated. Or horrific conflict ended.
But the world can be said to have advanced, despite a series of vicious — and too often genocidal — conflicts on several continents, and recurring economic crises that harm people everywhere.
Threats are the new norm
It may be that North Korea cannot be disarmed short of its destruction.
It may be that Iran is determined, by stealth, to arm itself with nuclear weapons and wreak havoc and terror throughout the Middle East on an even more massive scale.
But the question Mr Trump at the UN has posed is whether unilateral threats of nuclear war, and unilateral termination of nuclear agreements is the most effective way of resolving these and other crises.
And whether this brand of unilateral "diplomacy" — bellicosity, confrontation, execution — is the new norm.
Channelling his inner Elton John in demonising the tyrant who leads North Korea may bring Mr Trump as much satisfaction as the casual but calculated denigration of his political opponents at home — a ploy he believes helped win him the White House.
Tweets calculated to derogate and wound. If it wasn't so serious, it would almost be funny.