The Great Mosque of Brussels stands proud in the capital of Belgium, as well it might. For the site was a gift by then Belgian King Baudouin in 1967 to the Saudis.
The 1960s saw large numbers of Moroccan and Turkish people arrive in Belgium as guest workers, and the House of al Saud were keen to help provide a place for worship. King Faisal gifted not only the Great Mosque itself, but a pledge of secure cheaper oil supplies to Belgian companies.
The traditions and teachings it brought with it came from a very specific strain of Islam, and today the Great Mosque of Brussels is said to remain a centre of Saudi-funded Wahhabi preaching and Salafism.
How much contact the perpetrators of the latest atrocities in Brussels had with the mosque we don't yet know; we do, however, know that they had links to Isis and Isis have claimed them as their own. The Saudis claim they run the kingdom along the tenets of Wahhabi teachings, whilst Isis contend it has deviated from the supposedly true path
Previously the Saudi director of the mosque has said that no-one connected with the so-called Islamic State would be allowed in. But what we do know is that Isis claim radical Wahhabism as the ideological engine of their monstrous movement. Saudi Arabia, of course, rejects accusations that it has had anything to do with the rise of the so-called Islamic State.
In the maelstrom of the Middle East, one nation state's state-sponsored Wahhabism is simply another would-be caliphate's fanatical beliefs. The question is whether the presence of centres of Wahhabi teaching provide fertile ground for the seeds of radicalisation.
As early in the refugee crisis as last September, the Saudis reportedly offered to build 200 new mosques in Germany to facilitate the new Syrian refugees. They were supposedly to have been accompanied by Saudi-supplied and financed preachers, and madrassas (faith schools). These reports were later denied by the Saudis themselves, but significantly in the meantime Merkel's allies rejected the offer - saying that Germany needed "solidarity with refugees," not "a cash donation".
Of course, Berlin only had to look at what free Saudi mosques, preachers and mosques have done to radicalise Bosnia, once a centre of mild and mellow observance of the Islamic faith. Or the Germans could have looked at Pakistan, dramatically radicalised by the myriad Saudi-funded mosques and their preachers, often from an early age in madrassas that have replaced much of Pakistan's more secular schols, and similarly in Afghanistan, and today beginning to sweep through Bangladesh.
None of this is new to the British government. No two countries on earth know what's been going on better than the US and Great Britain. In return for massive defence contracts both countries have enjoyed guaranteed oil supplies since the notorious pact signed on Valentine's Day 1945 by President Roosevelt and King Abdulaziz of Saudi Arabia aboard a US destroyer on Bitter Lake in Egypt.
In return for guaranteed oil supplies, America pledged never to interfere with or become involved with Saudi Arabia's internal affairs. Thus the West has been unable to act on what many see as the interface between the kingdom and its radical Wahhabi clerical leadership.
As Europe scurries after the alienated, radicalised, often criminalised, people who pose this very immediate threat to our cities and way of life, has the moment come for our own governments to confront our relationship with the Saudis, even as that country tries to confront its own threat from Isis?
Many in Britain, and indeed Belgium, would claim that we need to pursue a new course that will refuse all compromise with a regime that allegedly fosters the export of practices which so many Islamic scholars condemn as an abuse and contortion of a precious faith which brings so much succour to so many.
This post first appeared on the Channel 4 News website here.