SOCHI - Russia launches the largest security operation in Olympic history on Tuesday with one month to go before Vladimir Putin kicks off the Winter Games in Sochi amid renewed fears of suicide bombings.
Army soldiers manning armoured vehicles and navy officers patrolling the Black Sea will join a 37,000-strong contingent overseeing the February 7-23 sports extravaganza that will spotlight Putin's 14-year reign.
The prestige project -- often referred to as the "Putin Games" and costing some $50 billion (37 billion euros) -- has already been blighted by snubs from Western leaders upset with what they see as Kremlin-backed discrimination against gays and the infringement of many other rights.
Railway station and trolleybus blasts that killed 34 in Volgograd last month meanwhile revived fears that Islamists from the nearby Caucasus will seek to wreak havoc on the globally watched event.
Putin responded to mounting diplomatic pressure over the weekend by easing the terms of a tough decree banning all forms of political protest in Sochi.
And Russia's answer to the threat of terror will be unveiled Tuesday when the feared Federal Security Service (FSB) takes charge of a security clampdown even fiercer than that seen at the 2008 Summer Games in Beijing.
"Starting January 7, all divisions responsible for ensuring the guests' security at the Games are being put on combat alert," Emergencies Situation Minister Vladimir Puchkov said.
"Every facility will be put under protection and a space-based monitoring system will be launched."
Additional measures deployed down the line will let the FSB monitor mobile phone and e-mail traffic while obliging all foreign visitors to register online.
Putin brought Russia's first post-Soviet Games to the palm tree-lined port against long odds in 2007 by personally telling Olympic chiefs in Guatemala that he would stage the best festivities they had yet seen.
That promise was soon followed by orders for Russia's titans of industry to transform Sochi's crumbling Communist-era skyline into that of a futuristic city worthy of the Gulf emirates.
The mission has been largely accomplished despite protests about the Games' environmental impact and reports of migrant workers being employed at illegally low wages and housed in inhumane conditions.
But Putin has been unable to duck the indignity of leaders from most big European nations and the United States snubbing the Games' opening ceremony because of Russia's new "homosexual propaganda" ban.
Washington will instead send a delegation featuring such openly gay and lesbian stars as Olympic figure skating champion Brian Boitano and tennis legend Billie Jean King.
"The US delegation to the Olympic Games represents the diversity that is the United States," US National Security Council spokeswoman Caitlin Hayden pointedly remarked.
Russian Olympic Committee chief Alexander Zhukov brushed off the absences as trivialities that "in no way affect the Olympic Games".
Putin did however bow to the International Olympic Committee on Saturday by partially reversing a blanket ban on protests in Sochi.
"We welcome this announcement," the IOC said.
"It is in line with the assurances that President Putin gave us... to ensure free expression whilst delivering safe and secure Games."
Security became an even bigger priority over the summer when a feared Russian Islamist vowed to unleash a campaign of terror against civilians that undermined Putin and kept all Sochi visitors at bay.
The deadly seriousness of the issue became ever more apparent with the twin December 29-30 bombings on the million-strong southern city of Volgograd -- a strike for which no one has claimed responsibility but that Russian media linked to Caucasus militants.
Putin called the attacks an "abomination" and assured the nation he would "fight against terrorists until their total destruction".
The strongman's rule has been tied throughout to Caucasus conflicts that began in Chechnya and have since spread across the mostly Muslim region that guerrillas want to turn into their own state.
But Putin has also been extremely sensitive about perceptions of Russia as weak, and has thus far baulked at security assistance offers from nations such as the United States.
The Pentagon reaffirmed on Saturday that it was ready to help in Sochi "if requested".
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