Revered, even feared, to the point where no one will contradict him; aloof, isolated, a digital hermit who is never out of touch; broadly supported, but very narrowly advised by an ever-tighter group of confidantes. This is the picture of Vladimir Putin and his leadership style painted by a number of people with knowledge of the inner workings of the Kremlin, at a time when such things matter more than at any time since the collapse of communism.

Putin's Ukraine actions this year have turned him once again into arguably the world's most fascinating leader. But just as Kremlinology comes back into vogue, the walls of Putin's central Moscow redoubt are becoming as opaque as they were during the time of Brezhnev.

One anecdote about Putin's Kremlin reveals a tantalising glimpse of what it is to be a presidential adviser. Putin himself receives briefing information on printed sheets inside red folders; he very rarely uses the internet. According to one source, requirements for his briefing notes have changed significantly in recent months. The president now demands notes on any topic to be no more than three pages long and written in type no smaller than 18 point.

But the number of people speaking truth to power is small. The majority of those in the Russian government, exasperated by the sharp western response to the six-month crisis, approve of Putin's actions in Ukraine. But those who disapprove have no forum in which to voice their doubts.

Putin himself gives few clues as to how he runs the shop. On Friday, he offered an elliptical answer to a question about leadership. "The main criterion for success is when a person has their own deep personal conviction in what they do. The task is not so that people are forced to follow your opinion, but to get your point of view across effectively. That is when people will become trusting and start to support you."

There is no question that Putin is supported by the elite, perhaps as never before. Evgeny Minchenko, an analyst who studies Kremlin elites, says that the security services, after a number of recent reshuffles and purges, are now "more loyal to Putin than at any time since he took power".

That doesn't mean the Kremlin is united. Former employees say the level of infighting is remarkable because of the extraordinary array of people working under one roof. "In a country like America where you have a two-party system, the majority of top decision makers would change depending on if it was a Republican or Democrat administration," one former Kremlin employee says. "But the Kremlin is full of people with completely opposing views. You can have people who believe in a fully state-controlled economy working on a project with people who are market-oriented liberals."

Far from finding this a problem, Putin relishes this, according to the source. "He likes it when his subordinates fight each other; he feels it makes him stronger."

Some are uneasy about the way policy has developed, but lack opportunities to voice their worries. Public dissent is a no-go area. A deputy economic development minister who referred to a government policy as "shameful" earlier this month was immediately fired; the more free-thinking members of the government have long been purged.

Putin's personality has dominated Russian politics in a manner not seen since the days of the USSR. Photograph: Alexander Nemenov/AFP/Getty Images

One of the few sources of information about how Putin's presidential administration works in recent months has been a blog published by a mysterious group called Shaltai-Boltai, the Russian name for Humpty Dumpty. The blog, which is now banned, has posted leaked Kremlin documents and emails, most recently claiming to have hacked the smartphone of prime minister Dmitry Medvedev, displaying some of his personal messages online and briefly hacking his Twitter account.

Other leaks have included information on how the Kremlin's east Ukraine strategy was planned and financed, or the texts of Putin's speeches, posted online before the president made them.

This being Russia, many have assumed that the leaks are organised by one Kremlin grouping keen to discredit another, though Shaltai-Boltai claim they are "idealists" who want to "change reality". The Guardian met one of the group recently, who identified himself only as Shaltai. On the appointed date, a man wearing a floral shirt appeared at the meeting place he had set, a river landing jetty on the outskirts of a European city, and agreed to speak only when the small boat he had provided was sailing and loud music was blaring to prevent anyone listening in.He said the group was made up of hackers and – perhaps – disgruntled officials, and had an entire archive of unused material that it may choose to release in the future.

He claimed the group had access to everything from the records of every meal Putin has eaten for the last few years to thousands of emails sent by top Kremlin officials. As evidence he plucked a laptop from a bag and opened what appeared to the full archive of an email account belonging to a leading Kremlin functionary.

Reading the emails and internal documents of the Kremlin has given the group a unique insight into the way Russia is run, said Shaltai, who described Putin as a man "without human emotions", who is nevertheless a genuine patriot with a belief that his rule is the best thing for Russia.

"I think he has been in power too long. He has grown detached. He really is like a tsar. Below him people are fighting amongst themselves, but they are too scared to disagree with him. He does not have friends in the normal sense. There may be people he likes, but he is extremely paranoid."

There are old school acquaintances and old judo partners who are part of the president's inner circle and gather for frequent games of ice hockey, but they do not generally play a role in matters of state.

Conversations with others familiar with the corridors of power suggest that recent key decisions have been taken in top secret and within a very small circle, coming as a surprise to almost all mid-level Kremlin officials.

Previously, the presidential administration would have round-table talks with experts on important issues, says Minchenko, the analyst. On Ukraine, these meetings have dried up since the new year, with decisions such as the annexation of Crimea and the current military intervention in east Ukraine being taken by a small coterie of advisers, most of whom have backgrounds in the security services.

"There were no discussions about it, no briefing notes, no focus groups," says Shaltai. "Two days before the decision to annex Crimea was made by Putin, almost nobody in the presidential administration knew anything about it."

Likewise, very few people have a real idea of just how far Russia's armed intervention in Ukraine will go. That, at least, is partly because Putin himself may not know. Putin, say Kremlin watchers, has not been acting according to a long-gestating atavistic plan to bring the Soviet Union back to life in recent months. Instead, he has felt forced into corners, and decisions like the annexation of Crimea were taken at the last minute, even if plans for the eventuality were already on the shelf.

"Putin is a conservative," says a former Kremlin official who knows him personally. "Making dramatic decisions is not his style. He is good with speaking aggressively, and is not 'politically correct' in the western sense. But with his actions, he has never been a fan of dramatic moves. This is why the last few months have been so surprising."

With its new cycle lanes, its hipster dining venues and its gentrified parks, Moscow does not feel like a city that is preparing for war. But scratch the surface in the corridors of power, and there is a very real belief in these apparently outlandish scenarios.

'He likes it when his subordinates fight each other; he feels it makes him stronger', says a Kremlin source. Photograph: Maxim Zmeyev/Reuters

Robert Shlegel, a pro-Kremlin MP, believes the US bombing of Moscow is a serious possibility in the not-too-distant future: "As a father I think every day about where I could evacuate my family to – to the Urals or Siberia," he told the Guardian. "It's a very real threat."

The international anger over the downing of MH17 over eastern Ukraine only compounded this sense of injustice in the Kremlin. In the period after the crash, with the world suspecting a Russian missile was involved in downing the plane, Putin spent days fielding angry phone calls from western leaders. Four days after the crash, he recorded a video address in the early hours of the morning, after an evening spent on the phone with various leaders. Putin was alone, standing by a desk, shifting his body weight from one leg to the other, and his face shiny with reflected light.

"No one has the right to use this tragedy to pursue their own political goals," said Putin, his voice quiet but imbued with barely concealed fury. Even though the Russian president presumably understood it was the Russia-backed rebels who shot down MH17, he firmly believes that events put in train by the US in Kiev are responsible for the chaos in eastern Ukraine, in which Russia was forced to intervene.

That sense of despair at a supposed dark western anti-Russian conspiracy is not new, but it is stronger than ever. One government official, in a private conversation, recently ranted about the west's interference in Russia: "Maybe we are barbarians, but only because you won't leave us alone to develop," said the official, claiming that for the last century the west has repeatedly pulled Russia back, in a number of conspiracies starting with the 1917 revolution.

Russia's perennially arrested development has been a long-running subject for the country's political thinkers: "Give the state 20 years and you will not recognise Russia," said the conservative prime minister Petr Stolypin in 1909. Stolypin did not get 20 years. He was assassinated at the opera in Kiev two years later, as the country spiralled into the abyss of war and revolution.

Putin is a keen reader of history and Stolypin is one of the historical figures Putin most admires. If he stands for another six-year presidential term in 2018, he will be on course to have spent 24 years at the helm.

Much of the policymaking over Ukraine has been aimed at preventing what is seen as a western-backed plot to undermine his rule; at getting his chance to make a real difference where Stolypin could not.

Whatever happens in Ukraine, few have any doubt that Putin will seek to spend another term in the Kremlin when his term runs out in four years. "I have no doubt that he will stand in 2018," says the former Kremlin adviser. "He has no reason to leave. He is popular, he thinks he is better than other candidates, he has a constitutional right to run, and he sincerely believes he is bringing a lot of good to the country."