Once again, the United States has struck in Baghdad.

President Trump authorized the assassination of Iranian General Qassem Soleimani, head of the Quds (‘Jerusalem’) Brigade and Abu Mahdi al-Muhandis, the leader of its Iraqi allies, the Popular Mobilisation Forces (PMF), together with five others near Baghdad airport on 3 January.

Trump threatened to follow this with another illegal invasion of Iraqi sovereign territory.

That would be a crime of aggression, for which American leaders could be tried if the US did not reject the International Criminal Court.

America’s allies which do accept the ICC’s jurisdiction, and make large claims about the international rules-based order, should be outraged at Trump’s wanton disregard of it.

The US Administration’s justifications for the Baghdad attack – whether by drone or helicopter – would fall over in any court.

The accusations are less about what Soleimani and Abu Mahdi had done but more about what they were expected to do.

They were ‘actively developing plans to attack US diplomats and servicemen in Iraq and throughout the region’, and America’s ‘decisive defensive action’ was aimed at ‘deterring future Iranian attack plans’.

Because the US unilaterally declared Iran’s Revolutionary Guards Corps a ‘designated terrorist organization’ in April 2019, killing the head of its elite Quds force could be claimed as an ‘act of self-defense’.

Soleimani, says Trump, is a terrorist.

The crisis developed after months of US provocation of Iran, false flag attacks in the Gulf and the Strait of Hormuz, and Iranian retaliation.

The destruction of Saudi oil facilities in September 2019 was blamed on Iran, but is now seen as more likely to be the work of Israel, whose regular bombings of Syria go mainly unreported.

With Iraq now in leadership transition, Quds and PMF have been cracking down on young anti-corruption demonstrators (who are likely to have CIA backing).

US airstrikes extracted disproportionate revenge from PMF for the killing of a single US contractor at an army base, and PMF militants stormed and besieged the US Embassy in Baghdad for two days.

Majority Shia support for PMF is expected to strengthen as a result of the assassination of its leader.

The timing of President Trump’s unilateral acts is never exquisite, but the more he is on the back foot, the more aggressive he becomes (as Barry Levine shows in All the President’s Women, 2019).

The latest revelations from JustSecurity.org show that it was Trump himself who withheld military aid from Ukraine, and this evidence confronts Senate Republicans who have defended him with new problems.

But Trump’s Defence Secretary declared after the protests at the Embassy in Baghdad that the US was ‘willing and ready’ for a pre-emptive attack on Iraqi militants.

Knowing Trump’s present mood, the game, Mark Esper said, had changed.

Iraq is merely the overture: the next move in Trump’s campaign for a second term is war with Iran.

That war has been contemplated for years under several Presidents, going back to Jimmy Carter in 1979.

He tried and failed to avenge the occupation of the US Embassy in Tehran and the hostage-taking of American diplomats during the Ayatollah’s revolution.

Although Iran is the last on the Pentagon’s list of seven Middle East countries to be overthrown or destabilized, past presidents who weighed up the costs – including Obama – decided against it.

But Trump understands that fighting America’s enemies is a vote-winner.

‘The only way he figures he’s going to get re-elected,’ Trump said of Obama in 2011, ‘is to start a war with Iran’.

He may now be making the same calculation about himself.

Because this would be a new war, not the one for which Congress approved funds for President George W Bush in 2001, Trump may have to fight for funds.

He will argue that this is a further extension of the ‘war on terror’, and hence does not need Congressional endorsement.

Senator Tim Kaine on 2 January introduced a War Powers resolution which would require a debate and a vote before the US goes to war in Iran.

Whatever happens, Trump will find himself proposing another unwinnable, probably catastrophic war, and the waste of billions more dollars and many more lives: exactly what he criticized Obama for doing.

Trump’s preferred option, no doubt, will be for Iran to over-react.

Foreign Minister Mohamad Javad Zarif has already castigated the US for its ‘rogue adventurism’, calling the Baghdad killings an ‘act of international terrorism’.

Depending upon what Iraq does after its three days of national mourning, and how Iran decides to respond, another US war of aggression for oil and power could begin.

No doubt Trump’s friends Putin and Xi, and some Western leaders as well, are trying to talk him out of it.

But decades of anti-Iran propaganda will be hard to reverse