While many are resigned to tougher security as just one more inconvenience in a city handicapped by overcrowded, ageing infrastructure, some have bristled, especially at a proposal to put surface-to-air missiles on civilian buildings.

In the Bow Quarter apartments overlooking the Olympic Park, proposed site for a missile battery, resident Claude Grongnet, 78, told Reuters: "I am very much against it."

"It is sending the wrong signal," the retired translator added, suggesting the emplacement would make the complex a target. "I don't think it's protecting us, when there are 700 flats."

Her scepticism echoes a suspicion among some that the deployment of missiles in city centre locations, apart from posing an unnecessary risk to civilian lives, gives al Qaeda more respect than it deserves and dents the Olympic spirit.

"How did something that was supposed to be a joyful celebration end up becoming a joyless and fearful cross between a North Korean Party Congress and a minor war?" blogged science writer Michael Hanlon in the Daily Mail online edition.

"It is supposed to be fun ... If, at any time, surface-to-air missiles are involved, you know it cannot be fun."

If given final approval, the plan for SAM batteries would be the first time anti-aircraft weapons have been deployed in London since the end of World War Two.

EXCELLENT VIEW

But a decision to install air defence weaponry in London would follow a precedent set by previous Olympic hosts. China deployed a battery of surface-to-air missiles a kilometre south of its showpiece venues for the Beijing games in 2008.

Greece placed dozens of U.S.-made Patriot missiles around Athens some weeks before the 2004 Olympics, the first summer games after the September 2001 attacks on the United States.

The defence ministry said in a leaflet sent to occupants on Saturday it had chosen a former water tower in the Bow Quarter as one of several proposed sites because it offered "an excellent view of the surrounding area and the entire sky above the Olympic Park."

At the complex, another resident, Alison Girdiefski, 49, a project manager, said there was more anger about a lack of previous communication than about the missiles themselves.

She added: "What if some terrorist got in here? We've set it up for them."

Another resident, Alejandra Perez, 27, an intern from Mexico, said: "I don't feel comfortable with the situation, but I guess if it has to be done, it has to be done.

"I didn't imagine we would have the Olympics next to my flat, and I certainly didn't think we would have missiles on the roof. It has increased my desire to get away during the Games."

Brian Whelan, who also lives at the site, said on his blog he was considering a legal challenge to the plan.

In itself, grumbling about Olympic security can be seen as a sign of how far the capital, bombed by al Qaeda in 2005, has recovered a sense of normality in the intervening seven years.

SKILLED BOMB MAKER

But while Western security services have become more adept at countering al Qaeda, the threat from the network has changed rather than disappeared, experts say

Al Qaeda remains active in Britain, and its offshoots, in places like Yemen, Somalia and north Africa, have increased in capability even as its south Asia-based core has declined in importance, officials say.

And al Qaeda still has at least one very skilled bombmaker with a track record of hiding devices from advanced aviation security. Ibrahim al Asiri is still believed to be at large in Yemen and, according to court testimony, he provided the bomb in the attempted bombing of a U.S. airliner which a Nigerian man tried to carry out on Christmas Day in 2009.

Some Western security sources say Asiri built the devices used in a 2009 suicide attack that narrowly failed to assassinate Saudi Arabia's security chief. He was also said to be behind a foiled plot to send two air freight packages containing bombs to the United States in October 2010.

Charles Farr, director general of the Office for Security and Counter-Terrorism at the Home Office (interior ministry), told a conference on April 25 that crime and disorder similar to Britain's 2011 summer riots are the most likely serious threats to the Olympics, although Islamist militants and al Qaeda offshoot groups posed a growing challenge.

Of the al Qaeda affiliates, he said: "All are now more important and more of a problem than they were a year ago. They no longer have to wait for al Qaeda Central to tell them what to do ... They have much more freedom to prepare on the ground."

Britain has been a terrorist target for many years, with its role in Iraq and Afghanistan as a leading U.S. ally, increasing the threat from Islamist militants.

Four young British Islamists killed 52 commuters in suicide bomb attacks on London's transport network in July 2005, the day after the capital was awarded the 2012 games.

U.S. businesswoman Emily Landis Walker, a former staff member of the 9/11 Commission who advises London companies and authorities on security, told Reuters the Olympic security authorities "really know what they are doing and have a very robust plan."

Of the SAM missile proposal plan, she said: "It does look a little sensational, but unfortunately the world we live in today is drastically different than 11 years ago."

(Editing by David Holmes)

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