When protesters took to Taksim Square in Istanbul last week, the initial focus of their concern was the plan to cut down 600 trees for a big development project in the one of the few green spaces remaining in the congested, pulsating core of the historic Turkish city.

Since then, however, the demonstrations have rapidly escalated, riot police have fired tear gas and water cannons and the unrest is now widely seen as a visible display of pent-up frustration with Prime Minister Recep Tayyip Erdogan.

To his critics, the leader of the Islamist-rooted Justice and Development Party (AKP) is seen as increasingly authoritarian, and presiding over what many secular-minded Turks fear is a creeping conservative social agenda.

That's not the image of Turkey that many Westerners have. They tend to see Turkey as a new-found but strong NATO ally that tries to be a bridge to the Arab world while also speaking out criticaly against its warring neighbour, Syria's Bashar al-Assad.

And Erdogan himself will have none of the dictator talk. He says he is not a "master, but a servant" of the people, and dismisses the 10,000 or so protesters who gathered in the square on the weekend as part of an extremist fringe.

Here's a look at the unrest that has seen thousands congregating, hundreds arrested and hundreds reportedly injured. It has become the largest anti-government disturbance to hit Turkey in many years.

When and why?

On May 28, a small group of mostly young protesters gathered in Taksim Square, a frequent and historic political rallying point, to try to block the removal of trees in the adjacent Gezi park.

The trees in that popular green space in the very un-green heart of Istanbul were to be cut to make way for a development that reportedly includes a shopping mall, a mosque and a rebuilt Ottoman-era military barracks.

People were already "seething" at the development plan, says Ariel Salzmann, an associate professor of Islamic and world history at Queen's University, Kingston, Ont. But when crews went to start the constuction, "which would involve cutting down the trees, that touched off everything."

The demonstration started as an "environmentalist-driven protest," says Reva Bhalla, vice-president of global analysis for Stratfor, a Texas-based geopolitical intelligence firm.

But the situation turned violent on Thursday evening, May 30, when police moved in and attempted to dismantle the sit-in. The situation escalated the next day when, Bhalla says, the main opposition party saw a political opportunity to exploit the demonstrations. High-level representatives of the Republican People's Party joined the protest.

"Even though the demonstration started out as a kind of save-the-trees campaign, a historical preservation campaign against the AKP because they didn't want this park to be converted to a big multi-use shopping centre, it very quickly just mushroomed into this very vitriolic anti-AKP, anti-Erdogan campaign where they were calling him a fascist, calling for the overthrow of the government and so on."

On May 31, protests spread elsewhere in Turkey, including the capital, Ankara.

The Stratfor analysis says the size of the protests needs to be kept in perspective.

"Many of the areas where protests were reported are also areas where the Republican People's Party would be expected to bring out a large number of supporters," the firm said in a written report. "The protests would be highly significant if they grow to the hundreds of thousands, include a wider demographic and geographically extend to areas with traditionally strong support for the ruling party."

Who's protesting?

The protest has drawn together groups and individuals who would otherwise rarely join forces.

"What's so interesting is the groups across the spectrum, and that's why it's very dangerous to say this is secular versus Islamist," says Salzmann.

She points to videos popping up on YouTube from Istanbul that show women in headscarves sitting on city buses cheering loudly for the young people trying to keep the park green.

Turkish Prime Minister Recep Tayyip Erdogan dismissed street protests against his rule as actions organized by extremists and angrily rejected comparisons with the Arab Spring uprisings when he spoke with media on Monday in Istanbul.Turkish Prime Minister Recep Tayyip Erdogan dismissed street protests against his rule as actions organized by extremists and angrily rejected comparisons with the Arab Spring uprisings when he spoke with media on Monday in Istanbul. (Associated Press)

These young people, who Salzmann says might otherwise be called "soccer hooligans," are sitting next to representatives of Istanbul's LGBT community working for gay rights.

"You have nationalist … Turks sitting next to Kurds, so it is producing on the ground this unity of people who would otherwise be actually very splintered."

Bhalla says amid the "real motley crew" of supporters, there are the traditional people one might expect to see.

"They come from that more staunchly secular camp that has deep-rooted grievances against the AKP and they've been increasinginlly sidelined in the past decade as the AKP has increasingly consolidated its power."

Other groups include liberal youth — many of them university students — and representatives of the moderate Islamist Gulen movenment, who Bhalla says have a complex relationship with the AKP but have also openly rebuked Erdogan.

Stratfor's analysis also notes that the growing dissent is not a simple Islamist-secular divide.

"A perception has developed among a growing number of Turks that [the AKP] is pursuing an aggressive form of capitalism that defies environmental considerations as well as Islamic values," it says.

This diversity, however, might not set this group up for a long future as a fortified protest.

"Because this is such a disparate group of opposition, that doesn't really bode well for its ability to cohere and unite behind a single personality or a single message," says Bhalla.

Why the frustration with Erdogan?

Erdogan has been prime minister for a decade, and last won re-election in 2011.

Salzmann says anger and discontent at the Erdogan's AKP government have been "going on for a long time now."

Erdogan, she says, "has become increasingly authoriatian and has used and abused his powers in a variety of ways … to repress his critics." She points, for example, to hundreds of people – including journalists – who have been jailed.

And then there are social policies that have also proved unpopular in some quarters.

Bhalla notes there are people who come from the secular camp who are very concerned with the gradual social transformation taking place "where laws are being passed like banning alcohol sales after 10 p.m., changing the attire of Turkish Airlines flight attendants and things like that that they feel are infringing on the kind of core secularist … principles of the state."

Will this become another Arab Spring?

Images of protesters in a central city square conjures memories of the Arab Spring and particularly the unrest grew in Cairo's Tahrir Square two years ago.

Erdogan flatly rejects any suggestion of a "Tahrir Square" moment in Turkey, and most observers appear to feel that he is correct in that assessment.

"While you do see this gradual dissent that has been building against the AKP, this should not be couched in some sort of Turkish Spring context or anything like that. This is not Tahrir Square," says Bhalla.

"There is a very important, [and] so far, silent majority in play here where the AKP has substantial support in the country.

"If you just look at the 2011 election results, they still have roughly more than half of the country that are still deeply committed to the party and who lack a credible political alternative to the AKP."

High school students chant slogans during a protest at Gezi park in Istanbul on Monday.High school students chant slogans during a protest at Gezi park in Istanbul on Monday. (Thanassis Stavrakis/Associated Press)

Salzmann considers the protests to be a "summer of discontent against the so-called Turkish model" —the example of a Islamist-rooted government but with a moderate, business-friendly and secular outlook .

But while the AKP has pushed the democratization agenda forward since the 1980s, Salzmann says it has now become a force against it with its unregulated zest for development.

Bhalla says while the current unrest won't likely put Erdogan at risk of "some sort of popular overthrow," it will become more difficult for him to silence his opposition and push forward with his presidential ambitions.

He has been looking for Kurdish support for a referendum that would clear the way to transform Turkey from a parliamentary system to a purely presidential one, with him presumably in that head-of-state role beyond next year, when elections are planned.

"The sight of protesters from the pro-Kurdish Pace and Democracy Party (known as the BDP) joining Republican People's Party supporters for the June 1 protests does not bode well for Erdogan's plan to rely on those votes in the constitutional referendum," Stratfor said in an analysis of the Turkish protests.

With files from The Associated Press