British government lawyers are checking out the legality of US bombers using Diego Garcia as an air base to attack Iran.

They are also investigating how much the Royal Navy can be involved in ‘clearing’ the Straits of Hormuz in the event of a blockade by Iran.

The silence over potential attacks on Iran in recent weeks should fool no one.

Behind the scenes, elaborate preparations are going on to ensure that if, or most likely when, Israel launches airstrikes on Iranian nuclear installations, Britain will be ready to give support to Israel and the US, which will weigh in on Israel’s side.

"Senior ministers are discussing how Britain would respond in the event of a military confrontation between Israel and Iran later this year," says the BBC's political editor Nick Robinson.

"I have learnt that UK ministers are discussing not just the possibility of a military confrontation but what role, if any, Britain might play and whether any involvement would be legal," he adds.

The background to this news is the talks taking place in Baghdad today with the UN Security Council members plus Germany. The talks are widely being promoted as seeking an alternative path to war, through more inspections of installations and diplomatic initiatives. Recently, Israel has become much quieter over its repeatedly stated intentions to bomb Iran. It now seems to have pushed the timetable back to next year. The US elections may be part of the reason.

Even the most gung-ho war monger must also have noticed that the Middle East is already sliding into further wars and confrontations, with the growing strength of al Qaeda in Yemen, the fighting in Syria now spilling over into Lebanon and Iraq wracked with sectarian instability.

These are all the legacy of the failed wars in Afghanistan and Iraq.

A new war with Iran carries fantastic risks. As NATO leaders met in Chicago this week, their tacit admission was that the Afghan war has failed and the government and army there will effectively have to be bankrolled by the western powers to the tune of $4 billion a year after most foreign troops have withdrawn.

It’s the kind of franchising of war which suits a US increasingly dependent on drone attacks and other remote devices to conduct its wars. The Afghan army and police will effectively be a proxy army maintaining the occupation of their own country in the interests of the western powers who will have removed their own troops out of harm's way.

But because war with Iran carries risks -- highlighted by the lost wars in Iraq and Afghanistan -- doesn’t mean that it won’t happen. Israel remains determined to destroy Iran’s government and is confident that the western powers will back it up, however reluctantly.

That’s what the British government -- as reported by the BBC -- is preparing for. The anti-war movement has to be just as prepared to oppose this threat of a new and potentially even more deadly war than those which has been so catastrophic over the past eleven years.