TOBIAS Ellwood, Tory minister for the Middle East, said he was “disappointed to see mass executions” in Saudi Arabia. The understatement, complying with half a century of UK policy, was chosen carefully.

Any response to the execution of 47 people on a single day – the highest number in the Gulf dictatorship since 1980 – has to balance Westminster’s military complicity in the House of Saud with paper-thin concerns for human rights.

The hypocrisy will fail to shock those well versed in the UK’s history of empire for economic gain, siding with oil-rich tyrants and amplifying the crimes of enemies while ignoring our own.

But the depth and longevity of UK connivance with the Saudi regime should shock us. Most recently it has bubbled to the surface in Yemen, where UK weapons and aircraft have been used in the Saudi campaign of bombing schools and targeting civilians; 22 million people require emergence aid.

Last year Westminster’s elite bowed its heads and lowered its flags to honour the passing of Saudi King Abdullah, who regularly received visits from his British royal counterparts.

Diplomatic cables released to Wikileaks in 2013 also suggested that the UK had promoted Saudi Arabia, one of the most abusive states on earth, to the UN Human Rights Council. As Parliament returns to the Palace of Westminster today, some opposition MPs are calling for an inquiry.

The £5.6 billion of UK arms sold to the Saudis since David Cameron came to power will now come under greater scrutiny than ever before. Yet blaming the current government would mistake the institutional links that bind the British and Saudi ruling classes.

Investigative journalist Andrew Feinstein unravels this tale in his explosive account The Shadow World. He reveals that the UK-Saudi arms pact was first sealed in 1965, when the UK’s biggest ever export deal sold 42 fighter jets with associated add-ons of corrupt “commissions”. Parliament secretary John Stonehouse, who was instrumental in arranging the deal, was later convicted for fraud.

The deals and bribes flowed into the 70s, with UK ambassador Willie Morris stating that Saudi princes were accustomed to taking a 20 per cent cut on national business dealings. This policy of mutual back-scratching was enshrined in the 1977 Cooper Directive, which encouraged “very substantial commissions” and avoiding inquiries into the flow of money and arms.

However, the real bonanza came in 1985 when the Al Yamamah £43 billion arms deal – “arguably the most corrupt transaction in trading history” – brought BAE, BP, Shell and the two governments together in an oil-for-arms corporate pact.

To celebrate this matrimony the England football team even visited Saudi Arabia in 1988, chartered of course by arms firm BAE. The following year The Observer reported bribery allegations surrounding the arms deal, leading to decades of intense legal strife.

The Serious Fraud Office (SFO) led attempts to reveal the truth. There were £6 billion in pay-offs placed into a tax haven surrounding the Al Yamamah deal. Former defence minister Lord Gilmour admitted bribes were paid. The Stokes Report was discovered, which advocated bribery for arms contracts.

In 2004, 386 boxes of slush fund accounts were discovered by the SFO of Saudi officials who received payments from BAE, leading to arrests but no charges. Pressure on the arms deal frustrated Saudi, UK and corporate interests, so Tony Blair personally intervened to shut the investigation down on the basis of maintaining arms ties with Saudi Arabia.

The Campaign Against the Arms Trade took the case to the High Court, which determined in 2008 that the decision was an “abject surrender to the threat” which was “an attempt by a foreign government to prevent the course of justice in the UK”. BAE was fined $400 million in American courts.

Given this history, the current government can only be “disappointed” in regards to mass executions. Any real dissent would challenge the deep ties that have bound the two establishments together for decades. It lies on the SNP, who have reiterated opposition to the arms deals, to provide real opposition.

But that doesn’t mean independence supporters can dodge difficult, related questions. Here are two without easy answers. Should Scotland trade with the world’s most abusive states? Selling weapons is not acceptable – but what goods are acceptable, if any, to sell? Does trade and open diplomacy legitimise the Saudi leadership or does it provide real opportunities for improving human rights?

On weapons I want an independent Scotland to reject the destructive global arms industry. That brings economic challenges. Are we brave enough to place human rights above economic self-interest? Can we prepare a development programme of new jobs, not just for Trident, but across the arms industry as a whole?

Our time will come soon. A war-ravaged world waits in hope.