A terrorism expert has warned that Royal, oil and RAF connections mean there is still no room for complacency about terrorism in the north east of Scotland.
By Ken Banks
BBC Scotland's news website
North East Scotland reporter
David Capitanchik said there are still very real dangers
As the fifth anniversary of the 9/11 twin towers attack reminds the world of the dangers, David Capitanchik stressed the need for constant alertness.
Aberdeen and Peterhead are major hubs of the oil and gas industry, and the Royal Family often stay at Balmoral.
Mr Capitanchik warned: "They are looking for soft targets."
Aberdeen is known as Europe's oil capital, Peterhead houses the St Fergus gas terminal, the Royal Family's Balmoral Castle and Birkhall are in Royal Deeside, and the RAF has bases at Lossiemouth and Kinloss.
Meanwhile, thousands of tourists are drawn by the entire area's history, wildlife, scenery and whiskies.
Aberdeen-based expert Mr Capitanchik is a renowned voice on terrorism and security.
He told BBC Scotland's news website: "We cannot afford to be complacent in this part of the world - we have to keep up the same level of security as anywhere else.
"It's reckoned this is one of the safer parts. We are far away from the centre, London.
"You cannot afford to take the view that because we live in a remote area a terror group will not decide it's a place to attack.
"We do have certain targets that are part of the critical national infrastructure."
He explained: "Counter terrorism is a very expensive operation.
"If as time goes on no attack happens there's a danger that resources get diverted elsewhere and we could be at greater risk.
The North Sea oil and gas industry is a key part of Scotland's economy
"Most of the major oil companies such as BP and Shell are aware of the need for heightened security."
Mr Capitanchik urged smaller companies to do likewise and take every precaution possible, rather than assuming they are not targets.
Of other dangers he said: "We have a special Grampian Police unit that looks after the Royal Family.
"The RAF could also be a target but they tend to be pretty well looked after.
"The Nimrods are a major arm in our role, so might make them or the people in the local vicinity vulnerable.
"Aberdeen Harbour is much better protected than it used to be, and the airport is pretty well protected.
"Universities and colleges need to keep an open eye on what is happening on their campuses.
"I do not know about any evidence in this part of the world, but extremist groups recruit on campuses."
He explained: "What 9/11 did was shock us into seeing that we too could have a serious problem.
"The 9/11 attacks really shook the world - novel terrorist ideas came as something of a shock.
"You should not be frightened to report anything you think is suspicious as people can be reluctant.
Security has been stepped in the years since 9/11
"There is a need for people to be more aware of what's going on around them.
"It could happen anywhere at any time. Who knows what's happening in remoter parts?"
On the tourist front, the north east of Scotland and Northern Isles are said to be vibrant in the wake of 9/11.
A spokesperson for VisitScotland told the BBC Scotland news website: "Scotland did experience a slight downturn in the number of visitors from America in the immediate wake of 9/11.
"But visitor figures have recovered since then and we are now seeing an increasing number of Americans choosing to come to Scotland on holiday.
"Scotland has long enjoyed strong connections with America, with some 11 million Americans currently claiming Scottish ancestry.
"The north east and Northern Isles hold a particular appeal for Americans."