OPINION: For all the sudden drama of the attacks earlier this month on Saudi Arabia's crucial oil and gas infrastructure, there has been comparative peace in the aftermath.

This says something about the resilience of oil markets and the lessening importance of Middle East crude.

But it is not all over by any means, as the condemnation of Iran by European leaders at the UN showed this week.

Donald Trump said initially the US was “locked and loaded” for its own missile attacks on Iran if Tehran was found to be the perpetrator of the attacks.

But precious little in terms of retaliation has happened, at least so far.

Of course the US president had promised in the run-up to his election three years ago that there would be less foreign intervention, not more.

He wants troops leaving rather than entering foreign war zones if at all possible, as he prepares to fight for a second term.

Hence, perhaps, his surprising desire to hold talks — cancelled at the last minute — with the Taliban over Afghanistan last month.

But Riyadh also perhaps does not have the support it once had in Washington a year after the assassination of Jamal Khashoggi, and because the US is not reliant on Middle East crude.

And while half of Saudi Arabia's production was knocked out in one fell swoop at Abqaiq and Khurais, the markets carried on relatively calmly.

Yes, Brent crude shot up 20% in value to $72 per barrel on the first day of proper trading after the incident occurred, but it was soon pulling back.

That was partly due to the speed with which the Saudis said they could get at least half of the production back on stream.

But it also reflects how the US now helps produce much of its own and the world’s crude via its vast shale riches.

So this attack was not the “unprecedented disaster” that one Wall Street analyst excitedly called it, but there are major implications.

The drone and missile attacks have certainly pointed up the vulnerability of Saudi production infrastructure and security.

Reliability was a watchword for Saudi crude and products, but some of the shine has surely been taken off this branding.

And can the country really rely on Trump to defend it militarily? Despite the bellicose words from the White House, Trump has so far pulled away from, not towards, war.

The attacks have certainly rattled the confidence of tanker owners in the Persian Gulf — and those Asian countries such as China and Japan that are heavily dependent on Saudi crude.

Diversification of supply and the need for larger national petroleum reserves could be the name of the game here in future.

Neither China nor India — another major importer of Saudi crude — has very large stockpiles of oil, but they do both have refineries that can handle unprocessed crude.

The attacks also raised questions over the timing of the Saudi Aramco initial public offering, which was scheduled before the end of the year.

Energy Minister Prince Abdulaziz bin Salman claimed Aramco had risen “like a phoenix out of the ashes".

But some investors will question the reliability and vulnerability of its prized oil and gas assets.

This incident may have hit Saudi Arabia’s self-image hardest.

It has helped illustrate that, post shale and amid the move towards lower carbon energy, the desert kingdom may not be as important to oil markets as it once was.

(This is an Upstream opinion article.)