By Jonathan Head
BBC News, Turkey
Turkey's President and Chief of Staff discussed the latest arrests
Investigations into an alleged attempted coup in Turkey in 2003 have led to the charging of 20 military officers in the latest tensions between the secular nationalist establishment and the governing AK Party, whose roots lie in political Islam.
Even in the very centre of Istanbul, you cannot avoid the military. The intimidating red and black signs depicting a soldier in silhouette that warn passers-by not to enter the restricted zones are found in every corner of this country.
Inside them, members of Turkey's one-million-strong armed forces live a secluded existence.
They have their own shops, hospitals, even hairdressers, to enable this powerful and unaccountable institution to insulate itself from the rest of society.
Throughout Turkey's modern history, the military has been a decisive force, overthrowing four elected governments.
As a senior officer, you are a member of an untouchable elite, even in retirement.
But membership privileges were suspended this week when special anti-terrorism units showed up at the doors of more than 40 officers and marched them off to the police headquarters in Istanbul.
Former Deputy Chief of Military General Ergin Saygun was among those detained
They included former commanders of the air force, the navy and the army.
They are being questioned in connection with the latest in a string of alleged plots and conspiracies so twisted and murky that the term "Byzantine" scarcely does them justice.
There are secret operations with names like "Blondie", "Moonlight" and "Sledgehammer" - plans that purportedly involved planting bombs in mosques and having a Turkish Air Force jet shot down, thereby justifying another military takeover.
And there is talk of a shadowy network known as Ergenekon, which links mafia bosses, assassins and CIA-sponsored counter-insurgency units in a scarcely believable web of subversion.
It does not help that many of the allegations are based on documents leaked to a small, campaigning newspaper called Taraf.
The paper's courage in exposing military misdeeds has won it many admirers, but it has been unable to explain where the documents come from or how the newspaper is funded.
In a country as addicted to conspiracy theories as Turkey, that has given sceptics plenty of ammunition.
Nor does it help that, after nearly three years and three indictments running to thousands of pages, the investigation has produced little hard evidence.
Yet dozens of people have been jailed and put on trial, some of whom seem unlikely plotters. They include journalists, university professors and - believe it or not - the head of a charity called the Turkish Santa Claus Foundation.
There are plenty of people here who fear what the pious men who now run Turkey would do if no longer inhibited by the threat of military intervention
So is this just a stitch-up by the government to wrong-foot its opponents?
That is what the opposition parties are claiming.
After all there is no love lost between the devout Muslims of the governing party and the rigidly secular officer class.
And yet there are many dark episodes in this country's history that make such wild conspiracies almost credible.
Hundreds of unsolved murders; thousands of cases of torture and disappearances during the war against Kurdish separatism; enough dirty tricks to make anyone at least a little paranoid.
There are plenty of people here (reasonable people who want to see the soldiers return to barracks) who fear what the pious men who now run Turkey would do if no longer inhibited by the threat of military intervention.
In Turkey, headscarves are banned in civic spaces and official buildings
Would the pulsating night-life in Istanbul, which is the envy of many European cities, be allowed to survive?
In some parts of Turkey, it is now impossible to buy alcohol. This in a country whose revered founding father Ataturk built a brewery as his first state-run industry.
And what about the freedoms women enjoy - unrivalled in the Islamic world - what would happen to them?
It is not Sharia law they worry about but more subtle pressures, like jobs and state business going only to observant Muslims.
Then you meet people like Mutlu Alkan, one of Turkey's most successful businesswomen, who is also on the board of the governing party.
She wears an Islamic headscarf which, under the existing laws, denies her access to universities and government buildings.
She says she respects secular lifestyles and happily serves alcohol to guests who want it, yet she burns with indignation over the restrictions on her lifestyle still upheld by the military and its allies.
Last month, the Prime Minister Recep Tayyip Erdogan recalled a humiliating incident two years ago when his wife was barred from visiting a friend in a military hospital because she was wearing a headscarf.
They keep a box at the reception desk there for women to leave the pins that hold the scarves in place, so that they can enter the hospital with looser, more acceptable head coverings.
Mistrust and fear
I have found that in Turkey people fall into one of two camps (there is not much middle ground).
Either you mistrust the military, believing it poses the greatest obstacle to the country's onward march towards democracy and eventual membership of the European Union, or you fear the religious convictions of the governing party and what they will do to Turkey's secular traditions.
Even the judiciary is split.
There are few genuinely neutral institutions here.
Whatever verdict the courts conjure up from the avalanche of allegations they are now wading through, you can be sure that at least half the country will reject it.
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