On the face of it – and certainly to the quarter of a million tourists stranded for the past week in hotels and departure lounges – it seems a merciful resolution to an absurd situation. Last night, after the Thai Prime Minister was forced from power, the People’s Alliance for Democracy (PAD) announced that it was calling off its action.

The yellow-shirted activists will retreat from the halls of Suvarnabhumi airport, and the three-month occupation of Government House in central Bangkok by the PAD will also come to an end.

To assume that Thailand is now at peace would be a mistake, however.

The spectacle of the past week – in which the tourism and export industries of an entire country have been held to ransom by a few thousand middle-class zealots – demonstrates the alarming transformation that has come over Thailand in the past three years.

From one of the most stable nations in SouthEast Asia, it has become a place where effective democratic politics has almost ceased to function.

The key question is how such a mob, with a few light arms at best, was able to occupy a key strategic installation such as an airport so easily and for so long.

If foreign soldiers or terrorists, such as the ones who attacked Mumbai last week, had stormed Suvarnabhumi airport, there is little doubt that the Thai police and Army would have fought against them. It was not that they could not keep out the PAD, but that they chose not to.

And this raises the crucial question – who is really running Thailand?

Despite its name, the PAD favours a constitutional restriction of democracy to reduce the influence of rural voters. The majority of voters may reject the politics of the PAD, but its apparent immunity in the past week shows that it has backing from institutions powerful enough to intimidate the police and the Army.

Who might they be? The answers one hears, even from the best-informed Thais, are vague and hard to prove. No doubt many of the PAD supporters are genuine in their disgust at the now-exiled Thaksin Shinawatra and the adulation that he won among the rural poor – but this does not explain how they were able so blatantly to flout the law.

Sondhi Limthongkul, the chief leader of the movement, is a wealthy media mogul, but he alone could not have sustained the PAD for so long.

Darker rumours – and they are little more than that – infer support within the powerful Thai monarchy, perhaps from Queen Sirikit, who has been notable for expressing sympathy for PAD members injured in clashes with the police. Her support for the movement, the speculation goes, is intended to counteract the influence that Mr Thaksin was said to have had over her son, the unpopular Crown Prince Maha Vajiralongkorn.

All of this is difficult even to talk about in Thailand, where the crime of lèse-majesté – defaming the monarchy – is punishable with prison sentences. Whatever the truth behind the sinister PAD, it will continue to exert its influence long after the unhappy tourists have gone home.

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