Vladimir Putin took the oath as Russia's president on Monday with a ringing appeal for unity at the start of a six-year term in which he faces growing dissent, economic problems and bitter political rivalries.
Outside the Kremlin's high red walls, riot police prevented protests by rounding up 120 people, including men and women in cafes wearing the white ribbons symbolizing opposition to Putin, a day after detaining more than 400 people during clashes.
But in the Kremlin, 2,000 dignitaries applauded Putin's every step down the red carpet into a vast hall with gilded columns, the throne room of tsars, where he was sworn in with his right hand resting on the red-bound Russian constitution.
"We will achieve our goals if we are a single, united people, if we hold our fatherland dear, strengthen Russian democracy, constitutional rights and freedoms," Putin said in a five-minute speech after taking the oath for the third time.
"I will do all I can to justify the faith of millions of our citizens. I consider it to be the meaning of my whole life and my obligation to serve my fatherland and our people."
The Kremlin's bells chimed, and the national anthem bellowed out at the end of a ceremony which was followed by the head of the Russian Orthodox Church blessing Putin and the president taking charge of the nuclear suitcase.
Although he has remained Russia's dominant leader for the past four years as prime minister, Putin, 59, has now taken back the formal reins of power he ceded to his ally Dmitry Medvedev in 2008 after eight years as president.
Parliament is expected to approve Medvedev, 46, as prime minister on Tuesday, completing a job swap that has left many Russians feeling disenfranchised two decades after the Soviet Union collapsed.
Putin is returning with his authority weakened by months of protests that have polarized Russia and left the former KGB spy facing a battle to reassert himself or risk being sidelined by the business and political elites whose backing is vital.
"We want to, and we will, live in a democratic country," Putin declared, evoking patriotic images of Russia as a great nation and urging people to show a sense of responsibility and national pride to make the country stronger.
He made no mention of the protest movement or any policy declarations in his speech.
Despite his pledge, riot police, nervous after battling protesters at an anti-Putin rally on Sunday, cracked down on the slightest sign of dissent on the streets of central Moscow, many of which were left almost entirely empty.
At least 22 protesters were led away when a crowd of more than 100 started shouting "Russia without Putin" near two luxury hotels 500 meters (yards) from the Kremlin.
"This shows that Putin is scared of dissatisfied citizens. Although there are not so many of us, there are not so few either," said 18-year-old student Pavel Kopilkov.
Dozens of others were detained by police on a boulevard near the route of Putin's motorcade to the ceremony, including some who had been sitting outside a French bistro wearing the white ribbon of protest on their jackets and coats.
A Reuters correspondent saw tables and chairs being overturned as the people were hauled away.
"This is shameful. This is not how you celebrate a holiday - this is how you celebrate seizing power," liberal opposition leader Boris Nemtsov said shortly after he was detained.
Moscow police said a total of 120 had been detained for staging unsanctioned pickets and most would soon be released. In Putin's hometown of St Petersburg, police detained a few people in a crowd of dozens at a protest on the central Palace Square.
PUTIN UNDER PRESSURE
Although the protests, sparked by allegations of electoral fraud, had lost momentum before Sunday's rally, they have given birth to a civil society that will press on with attempts to undermine Putin's authority by contesting local elections.
Many of the protesters are angry that Putin is extending his 12-year domination of Russia and fear he will stifle political and economic reform in his third term as president.
He is under pressure to show he can adapt to the new political landscape. Few think he has changed much, if at all.
He has eased up on the choreographed macho antics that long burnished his image in Russia, such as riding horseback barechested and shooting a tiger with a tranquilizer gun.
Harder to shake off will be his habit of seeking total control, as political rivals begin to gain status and a rising middle class demands more political freedom.
He has to quell rivalries between liberals and conservatives battling for positions in the new cabinet under Medvedev, who is swapping jobs with Putin. The outcome of the struggle could help determine how far reforms go to improve the investment climate.
The $1.9 trillion economy is in better shape than that of most European countries, but is vulnerable to any drop in the price of oil, the main export commodity. The budget is under pressure from Putin's lavish pre-election spending promises.
Putin has said he wants to attract more foreign investment by improving the business climate, reduce corruption and red tape, and end Russia's heavy dependence on energy exports. But he has not spelled out how he will do this.
As in the past, he is likely to use tough anti-Western rhetoric on foreign policy to drum up support if times get tough in Russia. But he never yielded his strong influence over foreign policy as premier, so a major policy shift is unlikely.