Iran's assault on Israel is naked aggression that could wreak havoc on the world economy... or worse, writes MARK ALMOND

It has started. Following Israel’s airstrike on key Iranian commanders in the Syrian capital of Damascus, the two weeks of ‘phoney war’ in which threats and counter threats were exchanged, have now ended.

Unlike previous skirmishes in which Iran waged war from behind its proxies of Hamas, Hezbollah in Lebanon and the Houthi rebels of Yemen, last night represented a significant escalation.

In a chilling development, the two dominant military powers in the Middle East have begun to trade punches directly, in a heavyweight bout that could wreak terrible havoc on each other, but also the world economy.

The arteries of global trade in oil and natural gas run through the region, as do Europe’s imports of goods from China, Japan and South Korea.

International shipping is imperilled like never before. We saw this yesterday when Iranian special forces seized an Israeli-owned container ship in the Persian Gulf.

Again, this was not an act of piracy committed by Iran’s proxies in the Red Sea – this was Tehran itself, committing an act of bald aggression.

Israel’s next move is critical. If the country’s Iron Dome anti-missile defence system blunts this onslaught by shooting down most of Iran’s drones and missiles, then maybe an opportunity could present itself in which tensions could ease.

But if Israel feels confident that it can go further and neutralise Iranian attacks, it may decide to go on the front foot.

Israeli Prime Minister Benjamin Netanyahu could strike at Iran’s launch sites and nuclear facilities before Iranian President Ebrahim Raisi can retaliate. But it is a big job.

Britain and the US have been trying to silence Yemen’s much-weaker Houthis for six months now – without success. Can either side back down?

The Revolutionary Guards, whose senior commanders were assassinated by Israel on April 1, are Tehran’s enforcers at home as well as abroad.

Amid the pressure that has forced the country’s mullahs to unleash their drones on Israel, they will find it difficult to step back from the brink.

The hardmen who keep them in power will push for the attack to continue, not just on Israel directly but on her allies, such as Britain and the US – their shipping and embassies will become prime targets.

Backing off now is not an option for either side, nor for Britain.

Prime Minister Rishi Sunak has committed UK support to its ally, and shouldn’t waver.

Any chink in Western resolve will only encourage hostile states beyond the Middle East, like Russia and China – big power rivals who eagerly await a window of weakness in which to further their own territorial aims. These are deeply, deeply worrying times.