By Liam Allen
BBC News Online
The UK is on its highest level of alert against terrorism
The twin suicide bombings in Istanbul that claimed 27 lives marked the first specific terror attack on a British target - but what are the implications for safety and security in the UK itself?
In recent months warnings of the danger of a terror attack on Britain have been widely reported.
The head of MI5, Eliza Manningham-Buller, has said the threat posed by al-Qaeda may remain for years.
Thursday's strikes on the British consulate and London-based HSBC bank building have emphasised more than ever that, behind the US, Britain has become one of the most likely targets of international terrorism.
Dr Magnus Ranstorp, director of the Centre for the Study of Terrorism and Political Violence at St Andrew's University, says the UK has "excellent preparations" for an attack.
But, he told BBC News Online, "we can't protect ourselves 100%".
We have to be aware that something may slip through at some time
Dr Magnus Ranstorp
At Andrew's University
"We have to be aware that something may slip through at some time. We have to be sociologically and pathologically prepared for that."
He says there has always been a risk of attack but suggests it is now "more elevated" in the UK than in other countries as a result of the Istanbul attacks.
He believes Thursday's devastation is more of a worrying sign for troops in Iraq than it is for members of the UK public.
But he acknowledges that a suicide attack in this country could be difficult to counter.
"Even if the terrorists use chemical and biological weapons, it will be a weapon of mass disruption", he said.
"It could be a car bomb or a suicide bomber - it's difficult to say."
Former intelligence officer Ellie Goldsworthy, of the Royal United Services Institute, is also worried about the difficulties in stopping suicide bombers.
She thinks the chance of repeat attacks on Britons in other countries are quite likely because they are seen as "soft targets".
Experts fear the threat of suicide bombers in the UK
She also believes that, in terms of specific attacks on this country, suicide bombings cannot be ruled out.
She said: "The UK doesn't have a history of having to deal with suicide attacks. We have a history of dealing with IRA terrorism which is quite different."
Guy Dunn, director of research for risk assessment group the World Markets Research Centre says a high-profile attack should not be ruled out.
In August a WRMC study ranked Britain 10th in the world for its vulnerability to a terrorist attack and described it as "the most prized target in western Europe".
Britain was the only country in that top 10 with the "potential to be attacked" rather than actually having been attacked.
"After the HSBC attack in Turkey and the attack on the World Trade Center then business is clearly a target", said Mr Dunn.
"Business in the UK is under threat whether that be a multi-national, a US-based business located in London or a small business."
Most experts agree the threat is largely confined to London.
Mr Dunn points to an al-Qaeda calling card of attacking high-profile buildings, none more so than in 9/11, as a reason why prominent London landmarks are under threat.
He says our capital has as many high-profile, recognisable buildings as anywhere else in the world offering serious potential for attack.
"What prize an attack on somewhere like the House of Commons as an attack on the symbolism of western democracy?"
But all the experts News Online spoke to urged the public to be realistic about the threat, pointing to the "excellent" security preparations in place in Britain.
As Dr Ranstorp puts it: "There is more chance of being run over by a car than being involved in a terrorist attack."