Isa Blumi is a senior lecturer at Stockholm University and author of a book published earlier this year – "Destroying Yemen: What Chaos in Arabia Tells Us about the World". It's a "superb" book according to a commentator on RT, the Russian propaganda channel, and Vanessa Beeley, a prominent defender of Syria's Assad regime, is no less admiring of its author. In posts on Twitter she describes Blumi as "wonderful" and urges everyone to watch a video of his "outstanding" talk on Yemen delivered at Copenhagen University last May.

Not everyone is so complimentary, though. A review posted on Amazon says:

"Apart from being flatly ridiculous, the book is polemical, moralistic, simplistic, and reminiscent of the worst of Trotskyist discourse and conspiracy theories."

One of Blumi's most absurd claims is that Saudi Arabia was bankrupt in March 2015 and went to war in the hope of plundering Yemen's wealth. Yemen, he told an interviewer on the Real News Network, has "considerable assets" including oil and natural gas.

Despite Blumi's repeated assertions about foreigners coveting Yemen's "wealth", plundering its resources would be of negligible benefit to Saudi Arabia's economy. Yemen is one of the world's poorest countries – poorer by far than its Gulf neighbours. It has only 0.2% of the world's known oil reserves and 0.1% of the natural gas reserves. Saudi Arabia, meanwhile, has 74 times more oil and 42 times more gas.

Simplistic explanations

In his introduction to "Destroying Yemen", Blumi cautions against simplistic explanations of the conflict there:

"Much as this war is marketed in simple terms, often evoking the binaries popular in the media, there are far more complex (and long-standing) issues at play in Yemen that need analysis ..."

Regardless of his own advice, in the remaining 300-or-so pages of the book he sets out one of the most simplistic interpretations imaginable. The war in Yemen, he asserts, is not the fault of Yemenis themselves but the result of "empire". By "empire", Blumi says, he means "a system of economic, political and cultural domination that has reigned supreme since the conclusion of World War II".

Much of the book is a historical account, from the 19th century onwards, of Yemen's interactions with "empire" and resistance to it. Framing the history in this way gives the impression that foreign powers viewed Yemen as a desirable prize when, most of the time, their interest was marginal. Even for the British at the peak of imperialism, Yemen was little more than a conveniently located refuelling stop on the sea route to India.

The most worrying thing about the book is its obvious appeal to those who like to fit wars into anti-imperialist narratives whether the facts justify it or not. We have seen this before with the Syrian conflict where Assad's defenders claim to know of a long-prepared western plan for regime change. The regime's supposed resistance to imperialism thus becomes an excuse for ignoring the repression of its citizens.

Similarly in Yemen, Blumi views the Houthi fighters who imposed their rule over vast swathes of the country as resisting "empire". Far from contributing to a better understanding of what is plainly a multi-faceted war, this obscures the reality rather than clarifying it.

As with the anti-imperialist narratives of Syria, Blumi supports his argument by claiming the public have been deceived about events in Yemen. He objects to talk of a civil war – even though that's what it was in the beginning and, to a large extent, still is. Calling it a "civil war", he says, is "one of the more egregious examples of manipulative reporting":

"Framing events in this manner attempts to place the blame for these catastrophes on Yemenis themselves, a way of reading events that is not politically neutral. Claiming Yemen's ills are self-inflicted strategically elides the role outside interests played in igniting and sustaining such violence. In fact, this war is much more usefully read as a continued foreign effort to subordinate Yemenis, long defiantly independent from the globalisation trends infesting the larger world."

Blumi's reluctance to accept that Yemen's wounds are even partly self-inflicted is little short of preposterous. Of course there are international dimensions too but lumping everything together under the all-embracing concept of "empire" is unhelpful, to say the least. It also masks a diversity of goals and interests among the participants.

The Yemen conflict has three main strands, overlapping to some extent, and each with its own complexities. First, there is the civil war itself. Secondly there is the regional dimension, primarily involving Gulf states, with Saudi Arabia and the UAE at its forefront. Thirdly, and less directly, there is the enabling role of western powers, in particular the US and Britain.

The civil war

At the root of the conflict is a struggle for power – by Yemenis, inside Yemen – triggered by the resignation of Ali Abdullah Saleh after almost 34 years as president. Saleh stepped down in 2012, very reluctantly, following months of street protests against his rule.

Under a deal brokered by the Gulf Cooperation Council with the UN's blessing, Abd Rabbu Mansour Hadi – who had been Saleh's deputy – took over the reins as "transitional" president. This was supposed to be for a two-year period while a new constitution was drafted, paving the way for presidential and parliamentary elections, but the process was never completed.

The fatal flaw in the "transition" plan was that it granted ex-president Saleh immunity from prosecution and allowed him to remain in Yemen plotting against Hadi. Hadi had no real power base and struggled to assert himself. Saleh, on the other hand, still controlled significant parts of the security apparatus.

This also created an opportunity for the Houthis, a marginalised element in the far north who had long-standing grievances and had waged six armed rebellions against the Saleh government between 2004 and 2010. (Blumi, incidentally, objects to describing them as rebels, which he views as part of a "strategy" for "delegitimising the role they play".)

Saleh's continuing machinations led him, eventually, to join forces with his former enemy, the Houthis. With support from Saleh loyalists, the Houthis were then able to capture Sana'a and drive out Hadi's government. Not content with controlling the capital and large parts of the north, the Houthis continued their advance southwards and by March 2015 seemed poised to take over the entire country. At that point the Saudi-led coalition launched its military offensive with the aim of restoring Hadi's ousted government.

The struggle inside Yemen, though, is not merely between two rival governments but, in the words of Gregory Johnsen, a member of the UN panel of experts, "a messy and multi-sided civil war, featuring the Houthis, what’s left of the Yemeni government, a southern secessionist movement, UAE proxy forces, and various different militias – some Salafi, some local, and some closer to criminal gangs – all vying to grab and hold as much territory as they can".

The regional dimension

For Saudi Arabia and its allies, fighting the Houthis is primarily a way of pursuing their quarrel with Iran. By treating the Houthis as Iranian proxies they can claim to be fighting Iran, but without the risks of confronting Iran directly.

Although the Houthis' relationship with Iran was rather tenuous in the beginning, the effect of the Saudi-led intervention has been to strengthen it. Even so, Iran's involvement in Yemen is still far less than in Iraq and Syria, while historically Saudi Arabia has been the chief meddler in Yemeni affairs.

The Saudi decision to go to war in Yemen can also be attributed, at least in part, to the ambitions of Mohammed bin Salman, the king's impetuous son. In January 2015, two months before the bombing of Yemen began, Prince Mohammed had been appointed as the kingdom's defence minister. Apparently eager to make his mark, he was a key figure behind the launch of Operation Decisive Storm – a military campaign that was supposed to be over in a few weeks but has now dragged on for more than three years and has since been renamed Operation Restore Hope.

The war has become a huge drain financially for the Saudis who were so confident of a swift victory that they embarked on it without a clear exit strategy. The history of their previous military involvement in Yemen should to have advised caution: Saudi Arabia fought on the losing royalist side during the republican revolution, it armed the southern separatists who were overwhelmingly defeated by Saleh's forces in 1994, and in 2009-2010 carried out airstrikes in support of Saleh's "Operation Scorched Earth" which was supposed to finally quell the Houthis (but didn't).

Saudi Arabia's main Gulf ally, the UAE is active on the ground in southern Yemen with the aim of bringing stability to the "liberated" areas (those outside the Houthis' control) but with limited success so far. The Emiratis appear less committed than the Saudis to restoring Hadi's presidency.

There are also signs that the UAE has wider goals beyond Yemen. In the course of the war it has established bases across the sea in Eritrea, Somalia and Djibouti which neatly fit with the UAE's long-term aim of becoming a significant military power in the neighbourhood.

Western powers

The United States has little interest in Yemen for its own sake; its involvement stems mainly from the way Yemen impinges on its pursuit of other key interests. One of those is US anti-terrorism policy in which Yemen figures because of al-Qaeda's presence. The other is America's long-standing commitment to the security and stability of the Arab Gulf monarchies, and its role in the war – in the form of arms supplies and logistical support – should be viewed primarily in that light.

Gulf rulers have traditionally seen the US as their main source of protection but the shock of the Arab Spring uprisings prompted them to focus more on protecting themselves and their foreign policies became more assertive, both diplomatically and militarily.

President Obama, meanwhile, had been seeking to shift the focus of US foreign policy away from the Middle East and more towards China and the Pacific rim, so this initially seemed like a welcome development. If GCC states were willing to take charge of their own security the US would be able to step back from the region. However, the GCC states' ability to do this still hinged largely on supplies of weaponry from the US and other western countries.

The Saudi-led offensive in Yemen is thus a prime example of the newly-assertive GCC states' attempts at regional policing and the US feels obliged to support it – though without any great enthusiasm.

Britain, the other major arms supplier, is in a similar position. It has long-standing relationships in the Gulf which are economically important. Currently, the British government is desperate not only to maintain these but to strengthen them in order to make up for other trade that will be lost as a result of leaving the EU.

Untangling the threads

There's much more that might be said, but the outline above should give some indication of the war's complexity and the diverse interests and objectives of its main parties. Bundling them together for ideological purposes under the buzzword of "empire" doesn't help anyone to understand what is going on or offer a realistic way forward out of the conflict.

Rather than trying to fit the war into some all-embracing theory, the need is to disentangle its various threads and reduce them to more manageable proportions with a view to resolving them step by step.