How terrorist attacks affect tourism
There's been an exodus of tourists from Tunisia after an Islamist gunman killed 38 - 30 of them thought to be British - in a single attack. Does that mean nobody will choose to go on holiday there for the foreseeable future?
Terrorism always aims to inspire the kind of fear that will get people to change their behaviour.
The fear of a repeat attack is one of the reasons 3,500 British tourists have left Tunisia since Friday. But some have said in interviews and on social media that they are determined to finish their holidays, to defy the attacker Seifeddine Rezgui.
The Foreign Office has updated its travel advice. "Further terrorist attacks in Tunisia, including in tourist resorts, are possible," it says, "including by individuals who are unknown to the authorities and whose actions are inspired by terrorist groups via social media."
"Short-term, it would put some people off," says Yeganeh Morakabati, an expert in risk and tourism at Bournemouth University. "Longer-term, people have short memories. A lot of people will forget."
But the Foreign Office had already warned of a "high threat from terrorism" in Tunisia before Friday's massacre. "Attacks could be indiscriminate, including in places visited by foreigners," it said, urging people to be "especially vigilant".
It specifically mentioned a prior attack on the Bardo Museum in the capital Tunis, which left 22 people dead in March.
"If it's a one-off attack, people forget," says Morakabati. "With Tunisia we've had, in a matter of months, two of them - sending the signal that it's frequent."
In its 2014 tourism market report, the Association of British Travel Agents found the popularity of a "number of popular holiday destinations were affected by political, social and economic unrest".
"The most prominent of these was Egypt which started the year  with high visitor numbers but suffered a significant drop-off due to political unrest leading to changes to Foreign Office advice for UK citizens," it added.
Egypt, which has experienced several years of political unrest, saw an average annual decline in UK visitor numbers of 18.5% from 2010 to 2014, according to the Office for National Statistics.
But no other major tourist destination frequented by Britons suffered in the same way. British visitors to Tunisia dropped from 423,000 in 2010 to 360,000 in 2011, the year of the so-called Arab Spring, in which pro-democracy activists toppled several countries' governments. The figure has since picked up, reaching 440,000 last year. However, the amount spent by UK tourists fell from £178m to £143m from 2010 to 2014.
"A very good way of getting people to go to destinations which have suffered at the hands of terrorists is to cut prices," says Simon Calder, travel editor of The Independent. "It does seem to lure the British back and I don't say that at all disparagingly. We can make a cost-risk analysis . As long as we know the risks, that's a reasonable thing to do."
"Look at it as a mathematical equation," says Morakabati. "Sometimes the attractiveness of a destination is higher than the level of risk."
She has just returned from a two-week work-related trip to Kabul, Afghanistan. "That doesn't mean there isn't any risk. It just meant that my will to go there was so much that I've happily taken the risk with it. That threshold is different between all of us."
There was strong growth in the number of UK nationals going to Morocco, rising from 308,000 in 2010 to 460,000 last year. This included a 51,000 increase in 2012, the year after the Marrakesh bombing, which killed 15 people.
After the London bombings of July 2005, in which 52 people died, the number of people visiting the UK did not decline, according to official statistics.
Overall, the figures suggest that the tourism industry in countries enduring long-term strife, such as Egypt, suffers more than those affected by individual terror attacks.
Even then, promoting individual destinations within countries can help overcome this, says Morakabati. "Egypt has in the past done isolated marketing with Sharm el-Sheikh. For many tourists, who are not so strong with geography, they might almost not see it as part of Egypt. So if something happens to Egypt, they see it as separate."
This has happened since the revolution of 2011, says Morakabati, with big cities, including Cairo, being seen as more at risk of attacks. But this ignores the fact that, in 2005, bomb attacks on Sharm el-Sheikh, which is on the Red Sea, killed 88 people.
But governments have a financial incentive to protect tourist hotspots.
On the Foreign Office website's colour-coded travel map of Egypt, Sharm el-Sheikh is a small haven of "green" surrounded by "orange", which advises against all but essential travel.
Colombia's boom in tourism in recent decades has coincided with increased security and a regular army presence on major highways and tourist hubs, such as the Caribbean city of Cartagena, even though the country's war with leftist guerrillas continues.
Similarly Mexico's tourist zones have been largely unaffected by the violence that has rendered other parts of the country ungovernable.
Calder thinks that Tunisia's tourism industry, which accounted for 15.1% of the country's GDP last year, will suffer in the short term and then recover. "There are still hotels," he says. "There are still close to half a million people dependent on tourism for their livelihood."
The direct contribution of travel and tourism to Tunisia's GDP was expected to grow by 3.6% a year until 2024, according to a report published last year by the World Travel and Tourism Council. This, of course, was before this year's attacks.
It's important to remember that not all tourists are the same. A 2003 study found that more experienced travellers, in search of exotic experiences, were more likely to dismiss the risk of terrorism.
The Wall Street Journal reported in 2010 that the chance of a Westerner being killed by a terrorist was about one in three million each year, the same as an American's odds of being killed by a tornado. It added that it was not "clear that the threat from terrorism is increasing", with the years between 2005 and 2009 representing "the second safest period on record since at least 1970".
The think tank Global Research found that, in 2011, US citizens were nine times more likely to have been killed by a police officer than a terrorist.
"To the extent we overreact to these incidents - allowing them to disrupt our economy and our way of life - we do little but increase the value to terrorists of committing them," Nate Silver, founder of the statistical information website FiveThirtyEight, has said.
Bali, in Indonesia, is another tourist hotspot to have been the victim of terrorist attacks, in 2002 and 2005. By the time of the 2005 attack, the Indonesian island had witnessed a 20,000 increase in British tourists from the previous year, according to figures from the Bali Tourism Office.
That progress was temporarily interrupted, with a 13,000 drop in 2006, but the tourism industry has since recovered with an increase in British visitors every year - and more than twice as many in 2014 as there had been a decade earlier.
"If I'm looking for a place where it's unlikely - though, of course, never impossible - that I might be the victim of a terrorist attack, I would probably get on the next plane to the Azores in the middle of the Atlantic," says Calder.
"However I would happily go to Egypt, to Turkey, to Tunisia because, although there's much more significant risk of a terrorist attack in those places than there is in most tourist destinations, the chances of being involved are still very, very small."
Attacks that targeted tourists
- Luxor (pictured) - 62 people, mostly tourists were killed at the Egyptian archaeological site in 1997; attack widely blamed on Islamist group, Al-Gama'a al-Islamiyya (although in 2013 the group denied its involvement)
- Bali - 202 people were killed and 209 injured in 2002 bombing attack on nightclubs on the Indonesian island; various members of Islamist group Jemaah Islamiyah were convicted and executed for the crime
- Sharm el-Sheikh - 88 people were killed in an attack on the Egyptian resort in 2005 by a group affiliated with al-Qaeda
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