The decision by the Gibraltar authorities to release supertanker Grace 1 will slightly ease tensions between Britain and Iran, but not for long.
Relations between the two states have been steadily deteriorating for the past eight months and the fear is that they will collapse altogether, as they have done repeatedly in the past.
The steady drift to the break down in Anglo-Iranian relations comes at a sensitive time and unfolds against a backdrop of a sharp escalation of tensions between Iran and the United States across the Middle East.
One reason why the capture of Grace 1 by British Royal Marines so infuriated the Iranians – and prompted the seizure of the British-flagged tanker Stena Impero in the Strait of Hormuz two weeks later – was because the British action had been carried out at the behest of the Americans.
Whilst the tanker issue appears to be on the point of resolution, wider disputes and tensions in the fraught Anglo-Iranian relationship are likely to sharpen in the months ahead as Iran adopts an increasingly strident posture in the face of pressure by the US, UK and Israel.
In view of the emotions invested in the volatile Anglo-Iranian relationship, the breakdown this time could be more dramatic and long-lasting.
An old story
The British-Iranian relationship is one of the most intriguing and enigmatic in international relations. It is highly emotive primarily because of the UK's former quasi-colonial role in Iran. Whilst Iran could never be colonised, nevertheless a prolonged period of national decline for the better part of the 19th century made the country uniquely vulnerable to the so-called "Great Game".
As Britain and Russia intensified their rivalry in the last quarter of the 19th century for influence and control over Central Asia and its periphery, Iran's embattled Qajar rulers surrendered much of their sovereignty to the encroaching superpowers of the day.
The fact that the British were far more successful than their Russian rivals at penetrating Iranian society – and manipulating Iran's sclerotic elites – has left a lasting impression on the Iranian psyche. The former British foreign secretary, Jack Straw, has aptly captured this enduring Iranian impression of British power in his book, "The English Job: Understanding Iran and Why It Distrusts Britain".
Since the Iranian revolution of 1979, Tehran has been trying to reset its international relations across the board. The key foreign policy priority has been to rebalance relations with the core Western powers, notably the US and the UK.
To that end, Iran has scored major successes in the past four decades. A brief glance at the Middle East's geopolitical map in 2019 demonstrates just to what extent Iran has emerged as the region's dominant power, undermining, and in some cases displacing, American influence.
The struggle against British influence has been no less intense, but much of it has been hidden and thus the resulting shift in the balance of power has been harder to detect. Iran's main contemporary grievances against Britain revolve around London's outreach to Iran's adversaries in the Gulf, in addition to the hopeless British quest of re-establishing a semblance of influence within Iran.
The big breakdown?
Anglo-Iranian relations have been inherently volatile for two centuries, but they became more fraught and unpredictable following the Iranian revolution in 1979. Most importantly, the contemporary relationship has unfolded against a backdrop of a steady, but consistent, shift in the balance of power.
Today, Iran is much stronger than 40 years ago. By contrast, Britain continues to decline, at least in geopolitical terms, as evidenced by the shrunken size of the Royal Navy and broader depletion of military strength.
Broader indices of national power have shifted too. Iran is a remarkably cohesive society led by an ideologically-driven state determined to not only transform the international balance of power, but equally important to displace the normative values in international relations which have guaranteed Western hegemony for two centuries.
By contrast, Britain is a divided society led by elites who are increasingly unsure of their place in the world. The divisions and polarisation and, by extension, the decline of the British establishment, is set to intensify following Britain's disorderly exit from the European Union in just over two months.
The bottom line is that Iran seeks to redefine the relationship with Britain, not so much to the point of placing it on an equal footing, but building up sufficient leverage to deter the UK from working closely with Iran's regional adversaries to Tehran's disadvantage.
But the shift in the balance of power – with Iran now stronger than the UK in some key aspects – does not mean that the British will sit on their hands as Iran continues to redefine the relationship by continually defying and challenging Britain.
Indeed, post-Brexit, some elements of the British establishment may try to soften the political and economic blows by taking sanctuary in the old colonial delusions.
Anglo-Iranian relations have collapsed in a big way on at least two occasions since 1979. The first breakdown occurred in 1989 in the wake of the late Ayatollah Khomeini's Fatwa against the British-Indian novelist Salman Rushdie.
The late Ayatollah Khomeini's intervention galvanised the British Muslim community in an unprecedented manner and it may be considered as Iran's first major interference in Britain's internal affairs.
The second breakdown occurred in November 2011 after Iranian students stormed the British embassy in Tehran following Britain's lead role in imposing nuclear-related sanctions on Iran.
The third major breakdown is an inevitability, and may occur sooner rather than later owing to the new British Tory government's ideological and political proximity to the Trump administration in the US.
But this time around expect the breakdown to be deeper, longer and much harder to resolve.
The views expressed in this article belong to the author and do not necessarily reflect the editorial policy of Middle East Monitor.