The decision by British Airways and easyJet not to use Sharm el-Sheikh airport is understandable in the aftermath of the bombing of a Russian plane.
Neither airline will use the airport until at least January.
Securing airports fully is difficult, particularly the staff and commercial entry points to airports in third world countries where employees are more prone to corruption.
The Egyptian authorities will be frantically trying to bolster security at Sharm but it is far from clear they will be able to do this to the satisfaction of western airlines.
But there are many countries around the world in which impoverished airport staff could be prone to corruption. If these places too fall prey to extremists intent on smuggling explosives on to jets, a range of destinations could become unsafe.
At the same time, tourism to Muslim countries from wealthy non-Muslim nations is already in danger.
In 2011 there was an explosion in the tourist heart of Marrakech and in June this year there was a massacre in Sousse. Both Morocco and Tunisia have traditionally been considered to be stable Arab states, but Tunisia had a revolution in 2010. It also experienced a massacre at a museum earlier this year, and there was a bombing of a presidential guard bus yesterday killing at least 12 people.
Egypt had also been relatively stable prior to the Arab Spring, which was naively welcomed in the West but which ushered in uncertainty and extremism in many places.
The growing instability is tragic on three levels. First, obviously, there are the immediate victims.
Then there is the wider trauma to the local populations.
But now there is the fresh tragedy that these countries could become no-go areas to Western tourists. Key swathes of their economies will collapse if so. That in turn could lead to a rise in extremism. They badly need our tourism.
Morocco is still safe but, sadly, there is a question mark over other Arab countries now. We can only hope this changes.