By Ralph Boulton

LONDON, July 9 (Reuters) - There can be few countries where the art of the coup is so finely honed as in Turkey, adapting as it does constantly to the spirit of the age, spawning over the decades its own enigmatic lexicon - the "Coup By Memorandum", the "Post-Modern Coup", the "Judicial Coup", the "e-Coup".

Now newspapers (largely pro-government newspapers it should be said), gorge on tales of coup plots dubbed `Glove', `Blonde Girl', `Moonlight' and devote pages to a shadowy militant group code-named "Ergenekon".

Two retired military commanders, supposed members of the group, have been arrested at their homes on military compounds; a bold step by civilian authorities against an army that jealously guards its privileged status.

Critics of Prime Minister Tayyip Erdogan call the arrests, also netting businessmen and journalists, a `revenge action' for moves by the conservative judiciary to shut his AK party on charges of Islamist subversion.

Ertugrul Ozkok, editor of Hurriyet, a newspaper critical of the government, suggested authorities were riding roughshod over judicial processes. If things are as they seem, he said, "none of us can feel comfortable any more. Any one of us can be taken from our homes and held in custody."

Erdogan, facing a possible court ban from party politics, might also rest uneasily these sultry July nights.

Some coups have shaken Turkey to the core, others brought more subtle change. All have dealt a blow to democracy. A 1960 military putsch sent a prime minister and two other ministers to the gallows. Four in the last 50 years have toppled governments.

Turkish political folklore is rich with other conspiracies supposedly involving the "Deep State" - a nebulous fraternity of militant nationalists in the security services, military, judiciary and civil service.

WHY SUCH A RICH "COUP CULTURE" IN TURKEY?

Perhaps it's something to do with the way the rails of Turkish democracy snake along so narrow a ledge.

To one side the abyss, the fear of division and chaos many Turks seem to carry within. To the other side the forbidding, towering heights of powerful and distrusting Pashas, or generals. At every tight turn the train will scrape against the granite face or teeter precariously towards the edge.

Now is such a turn.

The Pashas, through their Turkish military optics, see a nation seduced by Tayyip. Critics say the judiciary, civil service, universities, even the presidency and security services, are being opened to infiltration by Islamists. AK's move to allow the Muslim headscarf in universities only underlines the perils.

Erdogan denies any Sharia ambitions. His party, embracing economic liberals, centrists and nationalists as well as religious conservatives, has steered a soundly pro-Western course (arguably far more pro-Western than that of the `secularist' parties AK first swept from office in 2002 polls), winning international profile, building a strong economy and gaining support across the population.

And here, in Erdogan's success and popularity, lies the Pashas' dilemma.

In all their interventions and coups, the Pashas, for many the trusted safeguard of the secular order, have never acted flagrantly against popular will.

The 1971 "Coup by Memorandum" came as a relief to millions after months of political violence and strikes. The armed forces chief handed what amounted to an ultimatum to the prime minister to restore order or it would "exercise its constitutional duty". That did the job. The premier stepped down and a provisional cabinet under military supervision duly restored order.

The 1980 "September 12 Coup" followed a resurgence of streetfighting between leftists and nationalists. The tanks rolled this time, the streets returned to calm, politicians were rounded up and left to cool their heels at detention centres.

By the 1990s, rolling tanks along the streets was less acceptable. The Pashas, however, again saw themselves compelled to act to defend the secular state of Ataturk against a government espousing Islamist ideas.

This was the genesis of the 1997 "Post-Modern Coup".

Prime Minister Necmettin Erbakan fell cleanly to a campaign of pressure from the military in conjunction with business, the judiciary, media and political leaders. If a column of tanks did roll down a mainstreet somewhere, it was only by way of a salutary reminder of pre-post-modern days.

Democracy might have emerged that much stronger though, some say, if the Pashas had kept their nerve and allowed Erbakan to fall under the weight of his own folly.

POPULAR SUPPORT

Erdogan's hold on power is, in any case, surer.

Erbakan enjoyed only about 20 percent support when elected and his popularity had slumped in office. Erdogan garnered 47 percent support at the 2007 election after a tense wrangle with the General Staff that became known as the "e-Coup" affair.

Just before midnight on April 27, the armed forces General Staff posted a declaration on its website cautioning Erdogan, in so many words, against putting up his right-hand man, Abdullah Gul, as president.

Erdogan did the unthinkable and publicly, if courteously, admonished the military the following day. His gamble then in calling the 2007 election greatly strengthened his position. Gul was duly installed as president. Breathtaking events.

History suggests the greatest fear haunting the military at such times is that of division; division - ethnic and political - in the country and division in the armed forces themselves.

The image of the police officers encroaching on military domain to arrest two generals was poignant, even if entirely within the law.

Conspiracy theorists in Turkey - and there are very many - would see the only way out for the "Deep State" in first robbing Erdogan of his supreme weapon, his popularity.

This, then, is where the Ergenekon allegations, regardless of facts yet to be established, have for many the irresistible ring of truth.

Newspapers speak of a plan to unleash a campaign of mass protests, bombings and shootings this month pitching the country into chaos and turning the population against Erdogan.

Today brought an armed attack at the United States' Istanbul mission that killed three policemen and three gunmen.

The military would then be relieved of any internal debate and forced to intervene to rescue the country. Erdogan would be gone, the country saved from an Islamist threat and the military effectively restored to the position of privilege which has been eroded by democratic reforms in the last six years.

HEART OF TURKISHNESS

Appropriately, the name "Ergenekon" goes to the heart of Turkishness.

In Turkish mythology, Ergenekon was a deep valley in which the ancient Turks lived, trapped and isolated from the world for four centuries, until a grey wolf led them out through a hidden pass. Free then to thrive, they went on to defeat their enemies and take their rightful place as a noble nation.

Erdogan will know that if he abandons caution and submits too much to his Islamist wing, the population, those rising middle classes, will almost certainly turn against him.

The game will be up.

The Pashas' instinct and their role is to suspect the worst of the politician, but while they seek to `guide' events, they know confrontation could devastate the economy and leave them with a chalice they don't cherish. Beyond the General Staff, in the darker recesses of the Deep State, there may be those less temperate. Government and military, courts and commentators might do well to stay their hand.

(editing by Janet McBride)

AlertNet news is provided by